BBC OSWORD usage summary
			========================

This is a list of OSWORD calls which I am aware of, their parameters and
exit conditions. Please send mail to jgh@mdfs.net if you have any additions
to this list.

Note that the OSWORD protocol does not permit passing back values in the A,
X, Y, or Status registers for calls other than OSWORD 0. If a call is made
to a function that returns values that way, it cannot be guaranteed that
they will be returned on all systems. OSWORD calls with numbers greater
than &7F should contain the number of parameters to send in the first byte
of the parameter block, and the number of parameters to receive in the
second byte of the parameter block, inclusive of the first two bytes.

Hex Dec Function						First appears
------------------------------------------------------------------------------
&00  0  Input line						Acorn MOS 1.20
	This is called by the BASIC INPUT command.
	On entry:
		XY?0..1=>string buffer
		XY?2   =maximum line length
		XY?3   =minimum acceptable ASCII value
		XY?4   =maximum acceptable ASCII value
	On exit:
		Y is the line length (excluding CR)
		Cy=1 if Escape terminated input

	Note that this is the only OSWORD call that legally returns values
	in the registers.

&01  1  Read system clock					Acorn MOS 0.10
	This is called by the BASIC TIME function
	On exit:
		XY+0..4=current 5-byte system clock value.

&02  2  Write system clock					Acorn MOS 0.10
	This is called by the BASIC TIME command
	On entry:
		XY+0..4=new 5-byte system clock value.

&03  3  Read interval timer					Acorn MOS 0.10
	On exit:
		XY+0..4=current 5-byte interval timer value.

&04  4  Write interval timer					Acorn MOS 0.10
	On entry:
		XY+0..4=new 5-byte interval timer value.

&05  5  Read I/O processor memory				Acorn MOS 1.00
	On entry:
		XY!0=address to read from
	On exit:
		XY?4=the byte read

	Some systems recognise screen memory at &FFFExxxx and sideways ROMs
	at &FFFr8000-&FFFrBFFF.

&06  6  Write I/O processor memory				Acorn MOS 1.00
	On entry:
		XY!0=address to write to
		XY?4=byte to be written.

	Some systems recognise screen memory at &FFFExxxx and sideways ROMs
	at &FFFr8000-&FFFrBFFF.

&07  7  Generate a sound					Acorn MOS 0.10
	This is called by the BASIC SOUND command.
	On entry:
		XY+0..1=channel
		XY+2..3=amplitude or envelope,
		XY+4..5=pitch
		XY+6..7=duration.
	The channel parameter specifies what device to use to make the
	sound:
		&0xxx - internal sound system
		&1xxx - internal sound system
		&20xx - Watford Electronics Speech system
		&FExx - MIDI control
		&FFxx - BBC Speech system

&08  8  Define a sound envelope 				Acorn MOS 0.10
	This is called by the BASIC ENVELOPE command.
	On entry:
		XY?0 =envelope number
		XY?1 =length of each envelope step (b7=auto repeat pitch
			envelope)
		XY?2 =change of pitch in step 1
		XY?3 =change of pitch in section 2
		XY?4 =change of pitch in section 3
		XY?5 =number of steps in section 1
		XY?6 =number of steps in section 2
		XY?7 =number of steps in section 3
		XY?8 =change of amplitude per step in attack phase
		XY?9 =change of amplitude per step in decay phase
		XY?10=change of amplitude per step in sustain phase
		XY?11=change of amplitude per step in release phase
		XY?12=target amplitude at end of attack phase
		XY?13=target amplitude at the end of the decay phase

&09  9  Read screen pixel value 				Acorn MOS 0.10
	This is called by the BASIC POINT function
	On entry:
		XY+0..1=X coordinate
		XY+2..3=Y coordinate
	On exit:
		XY?4=pixel value, or &FF if the point was off screen or
			non-graphics screen mode.

&0A 10  Read character definition				Acorn MOS 1.00
	On entry:
		XY?0=character
	On exit:
		XY+1..8=the character raster data.

	The results for characters 0..31 and 127 are undefined.
	With MOS 3.00+ reading characters 0-7 reads the fill patterns
	defined with VDU 23,0-7.

&0B 11  Read palette						Acorn MOS 1.20
	On entry:
		XY?0=logical colour
	On exit:
		XY?1=physical colour
		XY?2=red component
		XY?3=green component
		XY?4=blue component

&0C 12  Write palette						Acorn MOS 1.20
	On entry:
		XY?0=logical colour
		XY?1=physical colour
		XY?2=red component
		XY?3=green component
		XY?4=blue component.

&0D 13  Read last two graphics positions			Acorn MOS 1.20
	On exit:
		XY+0..1=previous X coordinate
		XY+2..3=previous Y coordinate
		XY+4..5=current X coordinate
		XY+6..7=current Y coordinate.

&0E 14  Reads CMOS clock					Acorn Master MOS
	On entry:
		XY+0=function code
	0 - Return clock value as string
		On exit:
			XY+0..23=CR-terminated string in form
			"Day,DD Mon Year.HH:MM:SS".

	1 - Return BCD clock value.
		On exit:
			XY?0=year (&00-&99)
			XY?1=month (&01-&12)
			XY?2=date (&01-&31)
			XY?3=day of week (&01-&07, Sun-Sat)
			XY?4=hours (&00-&23)
			XY?5=minutes (&00-&59)
			XY?6=seconds (&00-&59).

		A year value of &80-&99 represents 1980-1999, a value of
		&00-&79 represents 2000-2079.

	2 - Convert BCD to string.
		On entry:
			XY+1..7=BCD value
		On exit:
			XY+1..25=CR-terminated string

&0F 15  Write CMOS clock					Acorn Master MOS
	On entry:
		XY?0=function code
		XY+1.. value to use.
	Functions are:
		8 - Set time to value in format "HH:MM:SS"
		16 - Set date to value in format "Day,DD Mon Year"
		24 - Set time and date to value in format
		"Day,DD Mon Year.HH:MM:SS"

&10 16  Network transmit					NFS
	On entry:
		XY?0   =control byte with b7 set
		XY?1   =destination port
		XY+2..3=destination station
		XY!4   =buffer start address
		XY!8   =buffer end address
		XY!12  =remote address for immediate operations
	On exit
		XY?0=zero if transmission failed to start

	Transmission must be polled with OSBYTE &32 (50). If the
	destination station is &FFFF, a broadcast will be sent, the eight
	bytes of data are in the control block at XY+4 to XY+11. If the
	port number is zero, an immediate operation is transmitted.

&11 17  Open or read network receive block			NFS
	XY?0=0 - Open receive block
	On entry:
		XY?0   =0
		XY?1   must contain &7F
		XY?2   =port to receive on
		XY+3..4=station to receive from
		XY!5   =reception buffer start address
		XY!9   =reception buffer end address
	On exit:
		XY?0=0 if no more space to open blocks, or number of opened
		reception block. Receive blocks can be 'wild', ie will
		receive from anyone if the port or station values are set
		to &00.

	XY?0<>0 - Read and delete receive block
	On entry:
		XY?0=receive block number to read
		XY!5=receive buffer start address
		XY!9=receive buffer end address
	On exit:
		XY?1   =flag from transmission block
		XY?2   =port received on
		XY+3..4=station received from
		XY!9   =updated to new address of buffer end

	Unread receive blocks must be deleted with OSBYTE &34 (52).

&12 18  Read argument block and restore protection mask 	NFS
	On exit:
		XY+0..1=station number
		XY+2.. =supplied data.

&13 19  Read/Write station infomation				NFS
	On entry:
		XY+0=function
		XY+1..=read or written data
	Functions are:
	 0 - Read file server number to XY+1..2
	 1 - Write file server number from XY+1..2
	 2 - Read printer server number to XY+1..2
	 3 - Write printer server number from XY+1..2
	 4 - Read protection mask to XY?1
	 5 - Write protection mask from XY?1
	 6 - Read user environment:
		XY?1=URD, XY?2=CSD, XY?3=LIB
	 7 - Write user environment:
		XY?1=URD, XY?2=CSD, XY?3=LIB
	 8 - Read local station number to XY?1
	 9 - Read number of arguments to XY?1 and size of argument block to
	     XY?2 for OSWORD &12 (18) above
	10 - Read extended error number to XY?1
	additional ANFS calls:
	11 - Read channel error occured on to XY?1
	12 - Read printer server name to XY+1..XY+6
	13 - Write printer server name from XY+1..XY+6
	14 - Read space in NetPrint buffer to
	15 - Read ANFS timeouts in seconds:
		XY?1=not listening
		XY?2=no reply
		XY?3=machine peek
	16 - Write ANFS timeouts in seconds, as above
	17 - Translate network number.
	On exit:
		XY?1=this net or &00.
		If XY?3=0, returns XY?3=file server net number.
		If XY?3=this net, returns XY?3=0.
		If XY?3<>this net, returns XY?3 unchanged.

&14 20  Various NFS/Network functions				NFS
	XY?0=0 - Communicate with fileserver
	On entry:
		XY?1=size of rest of block
		XY?2=0
		XY?3=function
		XY?4=0
		XY?5=0
		XY?6=0
		XY+7... contains rest of infomation
	On exit:
		XY?1=updated size of block
		XY?2=command code, 0 for ok <>0 to continue with another
			function
		XY?3=error code, 0 for ok <>0 for error, CR-terminated
			error string at XY+4
		XY+4.. contains returned data.

	XY?0=1 - Send text string to remote station.
	On entry:
		XY+1..2=destination station
		XY+3... string to send, terminated by CR or &00. The CR
			also gets sent.

	XY?0=2 - Generate error on remote machine.
	On entry:
		XY+1..2=destination machine.

&15 21  Read/Write mouse and pointer infomation 		Arthur
	XY?0=0 - Set pointer size, shape and active point
	On entry:
		XY?1=shape number (1-4)
		XY?2=width in bytes (0-8)
		XY?3=height in pixels (0-32)
		XY?4=ActiveX in pixels from left
		XY?5=ActiveY in pixels from top
		XY!6=>pointer shape data

	XY?0=1 - Define mouse bounding box
	On entry:
		XY+1..2=left coordinate
		XY+3..4=bottom coordinate
		XY+5..6=right coordinate
		XY+7..8=top coordinate

	XY?0=2 - Set mouse multipliers
	On entry:
		XY?1=signed 8-bit X multiplier
		XY?2=signed 8-bit Y multiplier

	XY?0=3 - Set mouse position
	On entry:
		XY+1..2=X position
		XY+3..4=Y position.

	XY?0=4 - Read unbuffered mouse position
	On exit:
		XY+1..2=X position
		XY+3..4=Y position

	XY?0=5 - Set pointer position
	On entry:
		XY+1..2=X position
		XY+3..4=Y position

	XY?0=6 - Read pointer position
	On exit:
		XY+1..2=X position
		XY+3..4=Y position

&16 22  Set screen base start					Arthur
	On entry:
		XY?0=screen type
		XY!1=>screen base
	If type b0=1, sets the screen used by the VDU drivers,
	if type b1=1, sets the screen displayed by the hardware.

&19 25  Output speech data					Watford Speech
	On entry:
		XY!0   =address of data
		XY?4   =flag
		XY+5..6=length of data
	If flag is 0 then the address points to a table of byte pairs that
	are output as though with Speech OSBYTE &19. 
	If flag is &8x then the address points to an ASCII string of words or
	allophones, terminated with <cr> or &00. The string will be spoken
	as with *TALK
	If flag is &Cx then the address points to an ASCII string of word or
	allophones of the length specified in the control block.
	Calls with flag set to &8x or &Cx, bit 3 of the flag sets the unknown
	word mode. If flag is &x0 unrecognised words are spoken letter by
	letter. If flag is &x8 unrecognised words are ignored and the call
	is passed to the vector at &0230.

&20 32  Acorn User Windowing System by Alan Blundell		AUWIN
	Depreciated call as can only pass 4-character string across the Tube.
	Use OSWORD &202 instead.
	XY?0=0 - Close all windows
	XY?0=1 - Close top window
	XY?0=2 - Release window
	XY?0=3..9 - Open window type 3..9
	On entry:
		XY?1=left
		XY?2=bottom
		XY?3=right
		XY?4=top
		XY?5=foreground colour
		XY?6=background colour
		XY?7=title bar colour
		XY?8=title bar background colour
		XY?9=edge colour
		XY?10=edge background colour
		XY+11...=CR-terminated title string

&20 32  Transfer data between Tube and I/O memory		TubeLink
	On entry:
		XY?0=direction 0=Tube to I/O, 1=I/O to Tube
		XY!1=Tube address
		XY!5=I/O address
		XY!9=number of bytes
	Extended I/O addresses are used. &FFrrxxxx specifies ROM &rr,
	&FFFExxxx specifies shadow screen memory.

&21 33  Execute code in I/O processor				TubeLink
	On entry:
		XY!0=I/O address
		XY?4=A register
		XY?5=X register
		XY?6=Y register
		XY?7=P register (only bit 0 significant - Carry flag)
		XY?8=semaphore byte
	On exit:
		If the code has been executed, the semaphore byte is
		incremented by one. Extended I/O addresses are used.
		&FFrrxxxx specifies ROM &rr, &FFFExxxx specifies shadow
		screen memory. Returned register values are returned in
		control block.

&22 34  Read printer buffer information (UtilRAM)
&23 35  Write printer buffer information (UtilRAM) 

&28 40  Read PRISMA information table				Prisma
	On exit:
		XY?0..1 = PRISMA-3 I/O base address (default is &FCB0)
		XY?2    = PRISMA-3 ROM version number
		XY?3    = PRISMA-3 hardware revision level
		XY?4    = PRISMA-3 private workspace base page
		XY?5    = Sideways ROM number
		XY?6    = PRISMA-3 current number of buffer pages

&29 41  Read PRISMA pixel value					Prisma
	On entry:
		XY?0..1 = X coordinate
		XY?2..3 = Y corrdinate
	On exit:
		XY?4    = logical colour of pixel at X,Y
		XY?5..7 = reserved
		XY?8    = &FF=pixel outside graphics windows
	If the *POINT command has been used, then OSWORD 9 (POINT) passes
	and returns the same information in XY+0 to XY+4.

&2A 42  Read PRISMA logical screen size				Prisma
	On exit:
		XY?0..1 = maximum X coordinate (width-1)
		XY?2..3 = maximum Y corrdinate (height-1)
	The size of the logical screen will vary with the parameter set
	by the *WIDTH command.

&2B 43  Read PRISMA colour palette				Prisma
	On entry:
		XY?0=logical colour
	On exit:
		XY?1=physical colour
		XY?2=red component
		XY?3=green component
		XY?4=blue component
	The palette read is that currently set for definition by the
	second parameter of the *PALETTE command.

&2C 44  Send VDU code direct to PRISMA				Prisma
	On entry:
		XY?0   = VDU code
		XY?1.. = VDU sequence parameters

	This call provides a fast means of sending a whole VDU sequence
	directly to the PRISMA-3. It is recommended that, where possible,
	machine code programmers use this entry in preference to using
	OSWRCH.

	OSWORD &2C is always directed at the PRISMA-3 and only the
	PRISMA-3 regardless of the setting of *TEXT or *GRAPHICS.
	OSWORD &2C can be used without upsetting characters currently
	in the VDU queue.

&2D 45  Read last two PRISMA graphics cursors			Prisma
	On exit:
		XY+0..1=previous X coordinate
		XY+2..3=previous Y coordinate
		XY+4..5=current X coordinate
		XY+6..7=current Y coordinate.

	The coordinates are returned with respect to the current graphics
	origin.

&2E 46  Read PRISMA base screen visible origin			Prisma
	On exit:
		XY+0..1=X coordinate
		XY+2..3=Y coordinate

	The coordinates are returned with respect to the current graphics
	origin. The coordinate returned is the bottom left hand corner
	of the BASE screen when the LOWER screen is disabled. When
	enabled, the LOWER screen will cover this point.

	The BASE screen co-ordinate in the bottom left hand corner of the
	visible screen will vary with the current zoom factor and with
	panning and tilting commands. The OSWORD &2E call can be used to
	return this co-ordinate.

&2F 47  Read PRISMA graphics origin				Prisma
	On exit:
		XY+0..1=X coordinate
		XY+2..3=Y coordinate

&30 48  Read PRISMA interrupt status				Prisma
	On exit:
		XY?0 = Event 32 enable status
		XY?1 = Upper screen status
		XY?2 = Base screen status
		XY?3 = Lower screen status
		XY?4 = Window overlay status
		XY?5 = Roller screen enable status

	This call returns the current booking status of the various
	routines executed by the PRISMA-3 on every field sync interrupt.
	Each byte is returned as zero if the associated routine is not
	booked, and returned as non-zero if the routine is booked.

&31 49  Direct call to PRISMA command				Prisma
	On entry:
		XY?0   = command
		XY?1   = number of parameters
		XY?2.. = command parameters

	Commands are:
	XY?0		XY?1	XY?2..
	  0 *BLANK	 0
	  1
	  2 *CENTRE	 2
	  3 *COLOUR	 1
	  4 *DOWN	 1
	  5 *FIELD	 0
	  6 *GENLOCK	 0 or 1
	  7
	  8 *GOPT	 1 or 2
	  9 *GRAPHICS	 0 or 1
	 10
	 11 *GTV	 1 or 2
	 12 *INIT	 0
	 13 *LEFT	 1
	 14 *OVERLAY	 1 or 2
	 15 *PALETTE	 1 or 2
	 16 *POINT	 0 or 1
	 17 *PROFF	 0
	 18 *RIGHT	 1
	 19 *ROLLER	 0 or 1
	 20 *ROTATE	 1
	 21 *SPLIT	 1
	 22 *TEXT	 0 or 1
	 23 *TZOOM	 1 or 2
	 24 *UNBLANK	 0
	 25 *UP		 1
	 26 *VKEY	 1
	 27 *WIDTH	 1
	 28 *WINDOW	 1
	 29 *ZOOM	 1 to 4
	 30
	 31 *FGRAB	 1 or 2
	 32 *HOLD	 1
	 33 *LEVEL	 1 or 2
	 34 *LPHASE	 1
	 35 *BUFFER	 1
	128 Extend or re-allocate working buffer
		XY?1=buffer address high byte in I/O memory
		XY?2=number of pages
	129 Define pixel translation table
		XY?1..2=translation table address in I/O memory

	This call provides a fast interface to all of the PRISMA-3
	*commands, except the *CONFIGURE, *GSAVE and *GLOAD commands
	which require string parameters. Errors are generated in the
	same way as the *commands.

	The count at XY?1 is the number of parameters passed to the
	call, not the number of bytes passed. A 16-bit parameter is
	passed in two bytes but is counted as one parameter. For
	instance, *ZOOM 5 is passed as 29,1,5,0.

&32 50  Read position of PRISMA-3 roller screen			Prisma
	On entry:
		XY?0 = screen number
			0: Upper screen
			1: Base screen
			2: Lower screen
			3: Window overlay (source area)
	On exit:
		XY?0    = screen number
		XY?1..2 = X coordinate
		XY?3..4 = Y coordinate

	This call returns the top left hand coordinate visible on each
	of the four screen areas. This call will only return correct
	results when programmed with widths of 2048 or 4096.

&33 51  Read/Write PRISMA overlay or nonvolatile memory		Prisma
	On entry:
		XY?0	 = command 0=Read overlay
				   1=Write overlay
				   2=Read nonvolatile memory
				   3=Write nonvolatile memory
		XY?1	 = Overlay/NVM page for definition
		XY?2	 = Overlay/NVM address
		XY?3	 = Number of bytes to transfer (1-12)
		XY?4..15 = Data

	The nonvolatile memory is organised as 32 pages of 256 bytes. The page
	allocation is as follows:
		 0-15 Default overlay definitions 0-15
		  16  Default standard resolution palette - Red
		  17  Default standard resolution palette - Green
		  18  Default standard resolution palette - Blue
		  19  Default standard resolution palette, normal BBC parameter
		  20  Default high resolution palette - Red
		  21  Default high resolution palette - Green
		  22  Default high resolution palette - Blue
		  23  Default high resolution palette, normal BBC parameter
		24-25 Reserved
		25-27 User applications
		28-31 System use

&36 54  Stop Press Routines					Stop Press

&40 64  Read mouse pointer and button state			AMX Super Art
	On exit:
		XY+0..1=graphics X coordinate
		XY+2..3=graphics Y coordinate
		XY?4   =text X coordinate
		XY?5   =text Y coordinate
		XY?6   =button state (~&80=cancel, ~&40=move, ~&20=execute)

&41 65  Miscellaneous graphics commands 			AMX Super Art
	On entry:
		XY?0=command number
		XY+1.. contains the arguments.

	Commands are:
	0 - Draw patterned block
	On entry:
		XY+1   =pattern number
		XY+2..3= left X coordinate
		XY+4..5=bottom Y coordinate
		XY+6..7= right X coordinate
		XY+8..9=top Y coordinate

	1 - Store area of screen
	On entry:
		XY!1=destination address
		XY?5=left text X coordinate
		XY?6=bottom text Y coordinate
		XY?7=width in characters
		XY?8=height in characters.

	2 - Restore area of screen
	On entry:
		XY!1=source address
		XY?5=left text X coordinate
		XY?6=bottom text Y coordinate
		XY?7=width in characters
		XY?8=height in characters.

	3 - Store area then draw window on screen
	On entry:
		XY!1=destination address
		XY?5=left text X coordinate
		XY?6=bottom text Y coordinate
		XY?7=width in characters
		XY?8=height in characters.

	4 - Pull down a menu
	On entry:
		XY!1     =data store address
		XY?5     =left text X coordinate
		XY?6     =bottom text Y coordinate
		XY?7     =width in characters
		XY?8     =height in characters
		XY!9     =text address
		XY+13..15=tick and options flags
	Text is stored as CR-separated strings, terminated by a zero byte.
	Tick and options flags are split into 12 low-order bits (legal
	selections) and 12 high order bits (ticks).

	5 - Select option from pull down menu
	On entry:
		XY?1   =left X coordinate
		XY?2   =bottom Y coordinate
		XY?3   =right X coordinate
		XY?4   =top Y coordinate
		XY+5..6=illegal options flags
	On exit:
		XY?0=the selection number, or 0 if no item was selected.

	6 - Shift AMX Art screen
	On entry:
		XY?1=X shift
		XY?2=Y shift.

	7 - Set Mouse coordinates
	On entry:
		XY+1..2=X coordinate
		XY+3..4=Y coordinate

	8 - Read AMX ROM details
	On exit:
		XY?1     =ROM number
		XY+2..3  =workspace address
		XY?4     =mouse flag (0=off, &80=on)
		XY?5     =pointer flag (0=off, &40=on)
		XY+6..7  =RAM pattern address
		XY?8     =status flag (b0-b3 keys generated by buttons,
			 b4-b6 button status, b7 mouse movement generates
			 cursor key motion)
		XY+9..10 =pointer X coordinate
		XY+11..12=pointer Y coordinate
		XY+13    =mouse sensitivity flag (b0-b2 X sensitivity,
			 b3-b5 Y sensitivity, b6-b7 device type flag)
		XY+14    =ROM version number.

&42 66  Sideways RAM transfer					1770 DFS/SRAM
	On entry:
		XY+0   =function
		XY!1   =main memory address
		XY+5..6=data length
		XY?7   =ROM number &00..&0F or &10..&13 for banks W, X, Y, Z
		XY+8..9=sideways address
	The functions are:
	&00 - Read from absolute address
	&40 - Read from pseudo-address
	&80 - Write to absolute address
	&C0 - Write to pseudo-address

&43 67  Load/Save into/from sideways RAM			1770 DFS/SRAM
	On entry:
		XY?0     =function as for OSWORD &42 (66)
		XY+1..2  =>filename in I/O processor
		XY?3     =ROM number as for OSWORD &42 (66)
		XY+4..5  =sideways start address
		XY+6..7  =data length - ignored on LOAD
		XY+8..9  =buffer address
		XY+10..11=buffer length. If the buffer address is zero, a
			default buffer is used in private workspace. If the
			buffer length is larger than &7FFF, then language
			workspace from PAGE to HIMEM is used.

&44 68  AMX Super Art ROM commands				AMX Super Art
	On entry:
		XY?0=manufacturer code (0=AMS)
		XY?1=command number
		XY?2=number of arguments to the command
		XY+3... contain the arguments
	Commands are:
		0 - *Buttons off
		1 - *Buttons XY+3
		2 - *Sensitivity XY+3 [,XY+4]
		3 - *Update
		4 - *Icon XY+3 [,XY+4, XY+5]
		5 - *Desk [XY+3, XY+4]
		6 - *Window XY+3, XY+4, XY+5, XY+6
		7 - *Pointer XY+3, XY+4
		8 - *Loop XY+3
		9 - *MovePointer
		10 - *ShowPointer
		11 - *HidePointer
		12 - *MCursor XY+3 (1=on, 0=off)
		13 - *Header
		14 - *MWindow XY+3, XY+4, XY+5, XY+6
		15 - *Pattern XY+3
		16 - *Spray
		17 - *Device

&45 69  Move/Swap memory					Aries B32
	On entry:
		XY?0   =function: 0=move, 1=Swap
		XY+1..2=source start address
		XY+3   =bank specifier &00 to &0F for sideways ROMs/RAMs
			and program RAM, &80 to &8F for sideways ROM/RAMs
			and video RAM
		XY+4..5=source end address
		XY+6..7=destination address
		XY?8   =destination bank specifier (as above)
	On exit:
		XY?9=return code:
			0 = ok
			1 = overlapping areas for swap
			2 = end before start
			3 = destination end >&FFFF
			4 = no RAM in bank 13 or 14.

&45 69  Digitise picture					RHE
	On entry:
		Control block ignored

&46 70  Allocated to BBC soft, probably unused.

&47 71  PrettyPrint text output 				SPROW
	On entry:
		XY!0 =>null terminated string to print
		XY!4 =>dictionary to use or 0 for default dictionary
		XY!8 =>special string
		XY?12=memory flag for string, &00=RAM, &80+ROM=ROM
		XY?13=memory flag for dictionary, &00=RAM, &80+ROM=ROM
		XY?14=memory flag for special string, &00=RAM, &80+ROM=ROM

&49 73  Integra-B Windows commands				Integra-B
	On entry:
		XY?0=command number
		XY+1... contain the arguments
	Commands are:
             0        WMSON     Initialise windows 
             1        WMSOFF    Terminate windows
             2        MSPTR     Mouse/Pointer On/Off
             3        AXIS      Axis Lock
             4        SENS      Change mouse sensitivity
             5        SHOWP     Display pointer on screen with store
             6        PLOTP     Display pointer on screen
             7        HIDEP     Remove pointer from screen
             8        MOVEP     Update pointer on screen
             9        AUTOP     Select auto pointer update
            10        DEFP      Define pointer icon and mask
            11        SELP      Select pointer to display
            12        READP     Read pointer and mouse buttons
            13        SETP      Set pointer position
            14        LOOP      Wait for buttons change, or input char
            15        FINDP     Read functional location of pointer
            16        WOPEN     Open window
            17        WSEL      Select window
            18        WCLS      Close window
            19        WSTO      Remove window from screen
            20        WRCL      Restore window back to screen
            21        WPULL     Pull window to top
            22        WPUSH     Push window to bottom
            23        WCLR      Clear window work area to pattern
            24        WHDR      Display window header
            25        WFTR      Display window footer
            26        WMOVE     Change window position
            27        WSIZE     Change window size
            28        WBARS     Display/update scroll bars
            29        WSCRL     Scroll window work area
            30        ICON      Display or read an icon
            34        MENU      Select option from a vertical menu
            35        CLRA      Clear screen area to pattern
            36        INVA      Invert screen area
            37        MOVEO     Move outline
            38        SIZEO     Size outline

&4C 76  Extended communications control 			TQCOM
	On entry:
		XY?0=operation code
		XY?1=port or protocol number
	Operations are:
	0 - Initialise port for protocol (and claim vectors required,
	    including &0234).
	1 - Return null terminated port/protocol text name at XY+2...

&4D 77 -

&4E 78  Initialise heap 					DVR
	On entry:
		XY+0..1=start address of the heap
		XY+2..3=size of the heap
	On exit:
		XY?0=heap handle.
		C is set and XY are preserved if the call failed.

&4F 79  Claim area from heap					DVR
	XY is a heap handle.
	On entry:
		XY+0..1=size of the area to allocate
	On exit:
		XY is the address of the block allocated
		C is set and XY are preserved if the call failed.

&50 80  Release area to heap					DVR 
	XY is a heap handle.
	On entry:
		XY+0..1=address of the area to release
	On exit:
		XY are preserved and C is set if the call failed.

&50 80  Read Real-Time clock					CDFS
	On exit:
		XY?0 = seconds 0-59
		XY?1 = minutes 0-59
		XY?2 = hours 0-23
		XY?3 = day of week 1-7, 1=Sunday
		XY?4 = date of month 1-31
		XY?5 = month 1-12
		XY?6 = year 00-99

&50 80  512-byte ADFS hard drive access
	On entry:
		XY=>OSWORD &72 control block

&51 81  Get maximum heap block size				DVR
	XY is a heap handle.
	On exit:
		XY+0..1=size of the largest block available.
		If the call failed, XY are preserved, C is set,
		and XY+0..1 is set to zero.

&51 81  Write Real-Time clock					CDFS
	On entry:
		XY?0 = seconds 0-59
		XY?1 = minutes 0-59
		XY?2 = hours 0-23
		XY?3 = day of week 1-7, 1=Sunday
		XY?4 = date of month 1-31
		XY?5 = month 1-12
		XY?6 = year 00-99

&51 81  HKSET Support						SEHK
	XY?0=reason code
	1 - read the news line
		On entry:
		XY+1/2=address to read up to 80 characters + <cr>
		On exit:
		XY+0=result: 0=ok, &FF=signal fault, &FE=no ack from hardware
	2 - read a chinese character definition
		On entry:
		XY+1/2=address to read 32 bytes
		XY+5  =&80 for absolute ROM address, &00 for character number
		XY+6  =byte 0
		XY+7  =byte 1
		On exit:
		XY+0=result:	 0=ok
				&FF=no character ROM found
				&F0=character ROM 0 not found
				&0F=character ROM 1 not found
				&E0=number in byte 0 and byte 1 out of range
	3 - get bytes from a page in remote memory
		On entry:
		XY+1/2 = data address
		XY+5   = &00 for teletext page, &80 for stock page
		XY+6   = Handle
		XY+7   = Start Row (0-24)
		XY+8   = Start Column (0-79 for stock page, 0-39 for teletext page)
		XY+9/A = Number of bytes to read
			 0-&7CF for stock page, 0-&3E7 for teletext page
		On exit:
		XY+0=result: 0=ok, &FF=signal fault, &FE=no ack from hardware
	4 - test remote hardware
		On exit:
		XY+0=result: 0=ok, otherwise a bitmap of the chapters with errors
			in, b0=error in chapter 1, b7=error in chapter 8.
	5 - print stock page to screen or printer
		On entry:
		XY+1    = &80=screen only, &C0=screen and printer
		XY+2    = Handle
		On exit:
		XY+0=result: 0=ok, &FF=signal fault, &FE=no ack from hardware
			&FD=no printer
	6 - get new stock/teletext page (slow)
		On entry:
		XY+1    = &00 for teletext page, &80 for stock page
		For a teletext page:
		XY+2    = Magazine      (0-&7)
		XY+3    = Page Tens     (0-&F)
		XY+4    = Page Units    (0-&F)
		XY+5    = Hours Tens    (0-&3)  Here and below is
		XY+6    = Hours Units   (0-&F)  the Time Extension
		XY+7    = Minutes Tens  (0-&7)  Usually fill
		XY+8    = Minutes Units (0-&F)  with zeros
		For a stock page:
		XY+2    = LS Byte Stock Code (BCD)
		XY+3    = MS Byte Stock Code (BCD)
			  eg to get stock 16 XY+2=&16, XY+3=0
			  Stock pages are numbered 0 to 399
		On exit:
		XY+0=result: &FF=signal fault, &FE=no ack from hardware
				otherwise, handle to refer to the page
				in future calls. 0=no more handles.
	7 - get new stock/teletext page (fast)
		On entry:
		XY+1    = &00 for teletext page, &80 for stock page
		For a teletext page:
		XY+2    = Magazine      (0-&7)
		XY+3    = Page Tens     (0-&F)
		XY+4    = Page Units    (0-&F)
		XY+5    = Hours Tens    (0-&3)  Here and below is
		XY+6    = Hours Units   (0-&F)  the Time Extension
		XY+7    = Minutes Tens  (0-&7)  Usually fill
		XY+8    = Minutes Units (0-&F)  with zeros
		For a stock page:
		XY+2    = LS Byte Stock Code (BCD)
		XY+3    = MS Byte Stock Code (BCD)
			  eg to get stock 16 XY+2=&16, XY+3=0
			  Stock pages are numbered 0 to 399
		On exit:
		XY+0=result: &FF=signal fault, &FE=no ack from hardware
				otherwise, handle to refer to the page
				in future calls. 0=no more handles.
		On entry:
	8 - enter HKSET in I/O processor

&52 82  Initialise file buffer					DVR
	On entry:
		XY+0..1=a heap handle
		XY+2   =access flags (&80=writable, &40=readable)
		XY+3   =file handle, or zero for a memory file
	On exit:
		XY is the buffer handle
		C is set and X contains a failure code if the call
		failed. Failure codes are:
			1 = Memory claim failed
			2 = OSGBPB call failed
			3 = access failed
			4 = EOF detected
			5 = Memory release failed (heap corrupt)

&52 82  Torch operation
&53 83  Torch operation

&53 83  Finish with file buffer 				DVR
	XY is a buffer handle.
	On exit:
		C is set and X contains a failure code if the call failed.
		All in-memory blocks are written to the file system.

&54 84  Flush file buffer					DVR
	XY is a buffer handle.
	On entry:
		XY+0=flush code:
			0=flush non-modified blocks, not including current
			block.
			1=flush all but current block.
			2=flush all blocks
	On exit:
		C is set and X contains a failure code if the call failed.

&55 85  Get bytes from file buffer				DVR
	XY is a buffer handle.
	On entry:
		XY+0..1=number of bytes to get
		XY+2..4=file pointer to the start of the data
	On exit:
		XY contains an address at which the data is found, which is
		guaranteed to stay until another get bytes call or a flush
		all blocks call.
		If the call failed, C is set and X contains a failure code.

&56 86  Put bytes to file buffer				DVR
	XY is a buffer handle.
	On entry:
		XY+0..1=number of bytes to put
		XY+2..4=file pointer to the data
		XY+5..6=address of the data
	On exit:
		C is set and X contains a failure code if the call failed.
		If the call failed due to insufficient memory, the file
		pointer, data address, and number of bytes left are updated
		to point the the unwritten part.

&57 87  Create new binary tree node				DVR
	On entry:
		XY+0..1=data address
		XY+2..3=size of the data
		XY+4..5=heap handle. If the data address is zero, a new
			node is allocated, but the data is not copied.
	On exit:
		XY contains the address of the node
		C is set if the call failed.

&58 88  Insert node into binary tree				DVR
	On entry:
		XY+0..1=address of the root of the tree
		XY+2..3=address of a data comparison routine
		XY+4..5=address of the new node
		The data comparison routine is called with two addresses on
		the stack (low bytes first), and should exit with the Z
		flag set if the data at the addresses compares equal, or
		the N flag set if the first item is less than the second.
	On exit:
		C is set if the node was already in the tree and was not
		inserted, in which case XY contain the address of the data
		in the tree.

&59 89  Delete node from binary tree				DVR
	On entry:
		XY+0..1=address of the root of the tree
		XY+2..3=address of a data comparison routine
		XY+4..5=address of the node to delete
	On exit:
		C is set if the node could not be found in the tree,
		otherwise XY contain the address of the old node.

&5A 90  Find node in binary tree				DVR
	On entry:
		XY+0..1=address of the root of the tree
		XY+2..3=address of a data comparison routine
		XY+4..5=address of the data to find
	On exit:
		XY contain the address of the node found
		C is set if the data was not found.

&5A 90  HADFS Sector read/write/access				HADFS
	This can be called by the user to perform an operation, or called
	by HADFS to access an external drive where a supporting routine
	should respond.
	On entry:
		XY+0..1 must contain &0600
		XY!2    =data address
		XY!6    =sector address with the drive number in the top
			 byte (ie XY?9)
		XY?10   =number of sectors to transfer
		XY?11   =call type and returned result code
	A supporting routine should only claim the call if the call type
	is <&80, and the drive number is the one supported. Call types
	to recognise (do NOT call these) are:
		1=write
		2=read
		3=disk size request
		4=format
		5=bye (ie, dismount - do NOT claim)
	User call types are:
		&80=read
		&81=write
	Result codes are as for OSWORD &7F (127) plus &FE=Drive not
	present. If any external support routines leave the call type byte
	unchanged, HADFS changes it to &FE, Drive not present. HADFS will
	not clash with DVR as long as HADFS is in a higher priority ROM
	socket than DVR is.

&5B 91  Traverse binary tree					DVR
	On entry:
		XY+0..1=address of the root of the tree
		XY+2..3=address of an action routine
		XY+4   =traversal order flag (0=forward search, &FF=backward).
	The action routine is called with the address of the current node
	in XY, and should return with C clear if the traversal is to be
	continued, or C set of it is to be aborted.

&5C 92  Balance binary tree					DVR
	On entry:
		XY+0..1=address of the root of the tree.
	 The tree is rearranged into a route-balanced tree.

&5D 93  Parse option patterns					DVR
	On entry:
		XY+0..1=address of a pattern list
		XY+2..3=address of a string list
		XY+4..5=address of a result list
		XY?6   =case-sensitivity flag (0=case sensitive,
			&FF=case insensitive)
	The pattern and string lists are lists of length-prefixed strings,
	terminated by a zero byte. The character * in a pattern matches any
	number of characters, and the character ? matches exactly one
	character.
	On exit:
		The result list contains one entry for each string in the
	string list. The entry is &FF if no matching pattern was found, or
	1--#patterns indicating the pattern matched by the string. In the
	latter case, a pair of bytes follow for each sequence of * and ?,
	indicating the start and end indices of the corresponding part of
	the string.

&5E 94  Get string with control character interpretation	DVR
	On entry:
		XY+0..1=address of a CR-terminated string
		XY+2..3=destination address (for a length-prefixed string)
		XY?4   =flags byte (&80=double quoted allowed, &40=single
		quoting allowed, &20=non-quoted characters allowed,
		&10=skip preceding space, &8=enable escape character
		processing.
	On exit:
		The address of the source string is updated to indicate the
		next part of the string to be processed.
		C is set if the string was malformed.

&5F 95  Read/write I/O memory across tube			ISMEC Monitor
	On entry:
		XY+0   =command: 0=read, 1=write
		XY+1..4=I/O memory address, b16-b31 ignored
		XY+5   =byte read or written
		XY+6   =ROM number or 128 for shadow screen

&60 96  Read Videodisk MSN and status byte			VFS
	Same format as ADFS call &70 (112).
	On exit:
		XY?0=Master Sequence Number
		XY?1=status byte: b7=Tube present, b6=Tube claimed by VFS,
		b5=LVROM controller present, b4=n/u, b3=n/u, b2=*OPT1 flag,
		b1=Bad Free Space Map, b0=IRQ pending.

&61 97  Read free space on VFS disk				VFS
	Same format as ADFS call &71 (113).
	On exit:
		XY!0=free space on current disk.

&62 98  Access LVROM controller 				VFS
	Same format as ADFS call &72 (114). Commands are:
		&00=Test drive ready
		&01=Seek track 0
		&03=Request status
		&08=Read sectors
		&1B=Stop/Start drive; stop if XY?9=0, start if XY?9=1
		&C8=Read F-code result from LVDOS
		&CA=Transmit F-code to LVDOS, XY?9=1,
			XY!1=>command string, XY!11=string length
	Results include:
		&00=Ok
		&02=Drive door open
		&03=Media error, eg disk dirty
		&05=Bad SCSI command

&63 99  Read last VFS error number				VFS
	Same format as ADFS call &73 (115).
	On exit:
		XY+0..2=sector error occured at
		XY?2=b5-b7=drive number
		XY?3 b0-b6=result code as in OSWORD &62 (98), b7=0 if
			error occured on a channel
		XY?4=channel number if XY?3 b7=0

&64 100 Read current F-code					VFS
	On exit:
		XY+0... contains current F-code command string
			terminated by CR.

&6E 110 Read byte from shadow RAM board				Watford 32K
	On entry:
		XY+0..1=address within RAM board
		XY?2=bank flag, b0=0 - &0000-&2FFF is main memory
				b0=1 - &0000-&2FFF is shadow memory
				b1=0 - &3000-&7FFF is main memory
				b1=1 - &3000-&7FFF is shadow memory
	On exit:
		XY?3=byte read

&6F 111 Write byte to shadow RAM board				Watford 32K
	On entry:
		XY+0..1=address within RAM board
		XY?2   =bank flag, as for OSWORD &6E
		XY?3   =byte to be written
	On exit:
		XY?3=former contents of memory location.

&70 112 Read master sequence number and status byte		ADFS
	On exit:
		XY?0=Master Sequence Number
		XY?1=status byte: b7=Tube present, b6=Tube claimed by ADFS,
		b5=hard drive controller present, b4=n/u, b3=n/u, b2=*OPT1
		flag, b1=Bad Free Space Map, b0=IRQ pending.

&71 113 Read free space on disc 				ADFS
	On exit:
		XY!0=free space on current disk.

&72 114 Read/Write MFM sectors					ADFS
	On entry:
		XY?0=0
		XY!1=address
		XY?5=command
		XY?6=drive number in b5-b7, sector b16-b20 in b0-b4
		XY?7=sector middle byte
		XY?8=sector low byte
		XY?9=number of sectors
		XY?10=n/u,
		XY!11=data length if XY?9=0
	This is a standard SCSI command block. The drive number in XY?6 is
	ORed with the current drive. Commands are:
		(&00=Test drive ready)
		(&01=Seek track 0)
		(&03=Request status)
		 &08=Read data
		 &0A=Write data
		 &0B=Seek track
		(&1B=Stop/Start drive; stop if XY?9=0, start if XY?9=1)
	On exit:
		XY?0=result
			&00=Ok
			&02=Drive door open
			&03=Media error, eg disk dirty
			&05=Bad SCSI command
			&04=Not ready
			&40=Write protected
			&48=CRC error
			&50=Sector not found
			&60=Bad command
			&61=Bad address
			&63=Volume error
			&65=Bad drive
			&6F=Abort

&72 114 Direct Cumana Electron DFS disk access			CDFS
	On entry:
		XY?0=control byte:
			b0: side select 0,1
			b1: drive 1 select
			b2: drive 2 select
			b3: 0=double density, 1=single density
		XY?1=command
		XY?2=track
		XY?3=sector
		XY?4=data
		XY!5=address
		XY?9=0 for returned result
	Commands are:
		 &04=Seek track zero
		 &14=Seek track
		 &50=Step in one track
		 &70=Step out one track
		 &80=Read sector
		 &A0=Write sector
		 b0-b1=step rate 6ms/12ms/20ms/30ms
	On exit:
		XY?2=new track
		XY?3=new sector
		XY?9=result
			&00=Ok

&73 115 Read information about last error			ADFS
	On exit:
		XY+0..2=sector error occured at
		XY?2=b5-b7=drive number
		XY?3 b0-b6=result code as in OSWORD &72 (114), b7=0 if
			error occured on a channel
		XY?4=channel number if XY?3 b7=0

&7A 122 Teletext commands					Teletext
	On entry:
		XY?0=command. The command is &00..&7F for Advanced
		Teletext commands, &80..&FF for standard commands:
	&00 - Read channel, returned to XY?1, 0=BBC1, etc.
	&01 - Set channel from XY?1, 0=BBC1, etc.
	&02 - Read record flag. Record in XY?1, returned flag in XY?2:
	    b0=HOLD, b1=received, b2=being updated.
	&03 - Set record flag, record in XY?1, flag in XY?2 as above.
	&04 - Read a Page Grabber record. XY?1 contains record. Returns
	    XY?2=magazine, XY?3=BCD page number, XY+4..5=sub-page,
	    XY+6..7=I/O address to store page.
	&05 - Set a Page Grabber record, entry details as above.
	&06 - Read number of rows to be captured to XY?1.
	&07 - Set number of rows to be captured from XY?1.
	&08 - Read header line status to XY?1: &00=header off, &01=header on
	    with clock, &FF=header on without clock.
	&09 - Set header line status from XY?1 as above.
	&0A - Read magazine for header display to XY?1. &FF means all
	    headers.
	&0B - Set magazine for header display from XY?1 as above.
	&0C - Switch off teletext interrupts.
	&0D - Switch on teletext interrupts.
	&0E - Clear all Page Grabber records.
	&0F - Read Television Service Data Packet
	On exit:
		XY?1=magazine for initial page
		XY?2=BCD initial page number or &FF if none
		XY+3..4=initial page sub-code
		XY+5..6=network group identity
		XY?7=Time offset from Universal Coordinated Time:
			b0=1, b1=half hour, b2=1 hour, b3=2 hours, b4=4
			hours, b5=8 hours, b6=add/subtract offset, b7=1.
		XY+8..10=BCD Modified Julian Time hi to lo
		XY+11..13=BCD Universal Coordinated Time hours, minutes,
			seconds.
	&10 - Clear Page Grabber record.
	&11 - Read Adapter status to XY?1: &00=on and connected, &01=on, no
		TV signal, &02=off, but connected, &FF=no adapter connected.
	&12 - Set Subtitle Enable flag
	On entry:
		XY?1=&00 to enable, &FF to disable,
		XY?2=subtitle magazine
		XY?3=BCD subtitle page.
	&13 - Set interrupt handling flag from XY?1: &00 to enable, &FF to
	    disable.
	&14 - Enter Tuning routine. Exited by pressing SPACE.
	&15 - Return time from TSDP.
	On exit:
		XY+1..9="HH:MM:SS" string
		XY?10=flag, &00=ok, &FF=no time found.
	&16 - Return date from TSDP.
	On exit:
		XY+1..12="DD/MM/YYYY" string
		XY?12=flag, &00=ok, &FF=no date found.
	&17 - Check CRC.
	On entry:
		XY+1..2=>page data in I/O
	On exit:
		XY?3=result, &00=no CRC, &01=CRC ok, &FF=CRC failed.
	&18 - Download file from teletext.
	On entry:
		XY+1..2=>filename in I/O
		XY!3=load address
		XY!7=exec address
		XY?11=magazine number
		XY?12=BCD page number
		XY?13=&00 - Load to memory at OSHWM, &01 - Load to file
				load address
		XY?14=&00 - Reset default table, &01 Don't reset tables.
	&19 - De-Ham a byte at XY?1.
	On exit:
		XY?2=De-Hammed nybble and result. b0-b3 contain nybble,
			b4-b7=%1111 - unrecoverable error
			b4-b7=%0xx1 - recoverable error
			b4-b7=%x1x1 - single bit error
			b4-b7=%0xx0 - no error.
	&1A - Set emulation mode.
	On entry:
		XY?1=characters per line to receive, 40 for TFS mode, 42
		for TTX mode. The two extra bytes at the beginning contain
		the magazine and row numbers.
	&1B - Read emulation mode.
	On exit:
		XY?1=characters per line that will be read, 40 for TFS or
		42 for TTX.

	&80 - Reload Last Page.
	&85 - Fetch Page.
	On entry:
		XY?1=page 100s
		XY?2=page 10s
		XY?3=page 1s
		XY?4=subpage 1000s
		XY?5=subpage 100s
		XY?6=subpage 10s
		XY?7=subpage 1s
	&86 - Chain page. Fetches the next page in a chain.
	&88 - Head of Chain. Follows the chain around until the head is
	    reached.
	&89 - Test Arrived.
	On exit:
		XY?1=result: &00=last page requested not arrived, &FF=last
		page requested has arrived.
	&8A - Unlock Page. When a page has arrived, it becomes locked. This
	    unlocks it and allows further update.
	&8B - Select Channel. Selects the channel in XY?1 (0-3).
	&8D - Read TSDP.
	On exit:
		XY+1..2=Television Service Data Packet.
	&8E - DeHam a Byte. The byte at XY?1 is dehamed and returned in
	    XY?1, with flags as for &19 above.
	&8F - Transfer. The current page is transfered to the address in
	    XY+1..4.
	&92 - Headers.
	On entry:
		XY+1..2=I/O address to display 32-character page header.
	&93 - What Channel. Returns the currently selected channel in XY?1.

&7B 123 Modem comands						Prestel Adaptor
	The Prestel adapter modem can be in one of five states:
	State 0 - on-hook, speaker off.
	State 1 - off-hook, speaker on, modem off.
	State 2 - off-hook, speaker off, modem off, dialing suitable.
	State 3 - off-hook, speaker on, modem disabled, checking progress.
	State 4 - off-hook, speaker off, modem enabled, data must be sent
	at 75 baud and received at 1200 baud. The modem calls are used to
	step through the five states and to monitor the dialling progress.
	On entry:
		XY?0=command:
		0 - RESET to state 0.
		1 - STEP to next state. Do not use in state 4.
		2 - PULSE. Send a dial pulse. Use in state 2.
		3 - START-DIGIT. Initialise to send a digit, use in state 2.
		4 - END-DIGIT. Terminate dialling a digit, use in state 2.
		5 - DCD-CHECK. Exits with result in XY?0:
			0 - unpowered or no carrier
			1 - powered in state 0, carrier present in state 4.
	To dial a number, STEP to state 2, for each digit, START-DIGIT,
	PULSE for the number, END-DIGIT, STEP to state 4.

&7B 123 Modem commands						COMMAND
	On entry, XY+0=command as follows:
	1 - Read status byte
	On exit:
		XY?0: b0=offline/online, b1=XOFF sent, b2=XOFF received,
		b3=carrier present.

	2 - Put byte to modem
	On entry:
		XY?1=byte to send

	3 - Get byte from mode
	On exit:
		XY?0=byte
		XY?1=255 if valid, 0 if invalid

	4 - Put string to modem
	On entry:
		XY?1=length
		XY+2.. contains string

	5 - Get string from modem
	On exit:
		XY?0=length read
		XY+1.. contains string

	6 - Read from remote computer
	On entry:
		XY?1=maximum length
		XY+2..3=maximum time in centiseconds
	On exit:
		XY?0=length of string
		XY+1.. contains string
	If RETURN not receieved within the time, a Timout error
	(103) is generated.

&7B 123 Move a block of memory					HDFS
	On entry:
		XY!0=source address
		XY!4=length
		XY!8=destination address
	 Works across Tube and between Tube and I/O memory.

&7C 124 Multiple-track single density FDC command		HDFS
	On entry:
		XY?0   =drive number
		XY!1   =address
		XY+5..6=start sector
		XY+7..8=number of sectors to transfer
		XY?9   =8271 FDC command as for OSWORD &7F (127)
	If the drive number is &FF the previously-used drive is used.

&7D 125 Read cycle number of disc				DFS, HDFS
	On exit:
		XY?0=cycle number

&7E 126 Read disc (or directory) size				DFS, HDFS
	On exit:
		XY!0=size of the current disc (or directory for
		HDFS) in bytes.

&7F 127 Single-track single density FDC command			DFS, HDFS
	On entry:
		XY?0=drive number
		XY!1=address
		XY?5=number of parameters in the 8271 FDC command
		XY?6=8271 FDC command
		XY+7... command parameters
	On exit:
		XY+8+num parameters=result

	If the drive number is &FF the previously-used drive is used.

	Some commands are:
		&4B=Write sectors
		&53=Read sectors
		&63=format track
		&69=Seek track

	Results returned are:
		&00=ok
		&08=Clock error
		&0A=Late DMA
		&0C=CRC error in ID
		&0E=CRC error in data
		&10=Drive not ready (shouldn't occur)
		&12=Write protected
		&14=Track 0 not found
		&16=Write fault
		&18=Sector not found
		&FE=8271 command unknown

	Some systems extend the drive number to %pxDDddsd.
		p   selects the previously-used drive
		DD  select the drive density:
			%0x=current density
			%10=FM
			%11=MFM
		ddd select the drive
		s   selects the side.

&80 128 IEEE Commands						IEEEFS
	On entry:
		XY?0=send block length
		XY?1=receive block length
		XY+2=IEEE command
	On exit:
		XY+2... returned results.

&80 128 Springboard DOS INT					Springboard
	On entry:
		XY?0=24   (send length)
		XY?1=24   (receive length)
		XY+2..3  =INT number
		XY+4..5  =AX
		XY+6..7  =BX
		XY+8..9  =CX
		XY+10..11=DX
		XY+12..13=SI
		XY+14..15=DI
		XY+16..17=DP
		XY+18..19=ES
		XY+20..21=FLAGS.
	On exit:
		XY+4... returned 80x86 registers.

&81 129 Springboard, read address of PC parameter block	Spring
	On entry:
		XY?0=0 (send length)
		XY?1=10 (receive length).
	On exit:
			returned parameter block address

&82 130 Read/Write parameters					Cambridge ring

&83 131 Data transmission					Cambridge ring

&84 132 Ring polling						Cambridge ring

&85 133 Springboard						Springboard
	On entry:
		XY?0=4 (send length)
		XY?1=6 (receive length).

&86 134 Springboard						Springboard
	On entry:
		XY?0=6 (send length)
		XY?1=0 (receive length).

&89 137 Read teletext pixel					Dump Out 3
	The control block is incorrectly defined for the OSWORD protocol,
	and will work incorrectly if called from a coprocessor.
	On entry:
		XY+0..1=X coord 0-1279
		XY+2..3=Y coord 0-1024
		XY?11  =&FF on first call to check for double height
	On exit:
		XY?4     =Pixel colour or &80 if off-screen
		XY?5     =Y position with character cell
		XY?6     =foregound colour
		XY?7     =background colour
		XY?8     =character column containing pixel
		XY?9     =character row containing pixel
		XY?10    =character containing the pixel
		XY+11..13=double height table
		XY+12    =attribute: b1=held separated, b2=separated,
			 b3=hold, b4=conceal, b5=double height, b6=graphic,
			 b7=flash
		XY?15    =current hold character.

&8A 138 Set teletext pixel					Dump Out 3
	The control block is incorrectly defined for the OSWORD protocol,
	and will work incorrectly if called from a coprocessor.
	On entry:
		XY+0..1=X coord 0-1279
		XY+2..3=Y coord 0-1024
		XY?6=plot number:
			69=plot foreground
			70=invert
			71=plot background
			b7=1 to force overwriting of text
	On exit:
		XY?4 =X position within cell
		XY?5 =Y position within cell
		XY?8 =text column containing cell
		XY?9 =text row containing cell
		XY?10=character containing the pixel.

&90 144 "Service interface - Network"

&A0 160 "Isolated word recogniser"

&B0 176 GoMMC access & control					GoMMC
	On entry:
		XY?0   =send length
		XY?1   =receive length
		XY?2   =command
		XY?3   =subcommand
		XY?4   =&01
		XY?5   =&00
		XY+6...=data
	On exit:
		XY?4   =&00 if call actioned
		XY?5   =result byte
		XY+6...=data.

	Commands in XY?2 are:
	1 - Read GoMMC status, subcommand in XY?3
		XY?3=&01 - return GoMMC ROM number in XY?6
		XY?3=&02 - return MMC card size in XY!6
	2 - ?? - Returns data in XY+5
		XY+3=&09 - ?
		XY+3=&0A - ?
	3 - Read/Write data to current disk
	On entry:
		XY!6 =address
		XY!10=MMC address
		XY!14=data length
		XY?3 =&00 - Read data from current disk
		XY?3 =&01 - Write data to current disk
		XY?3 =&40 - Read data from absolute MMC address
		XY?3 =&41 - Write data to absolute MMC address
	4 - Read/Write data to current disk
	On entry:
		XY!  =address
		XY!10=MMC address
		XY!14=data length
		XY?3 =&00 - Read data from current disk
		XY?3 =&01 - Write data to current disk

&B2 178 Advanced BASIC (BASIC V) support			AdvBASIC
	This call is used to support 6502 BASIC V on the 6502 second
	processor.
	On entry:
		XY?0=send length
		XY?1=receive length
		XY?2=command
		XY+3.. additional information

	Commands in are:
	&00 - Read EDIT/ROM values
	On entry:
		XY?0=3 (send length)
		XY?1=3 (receive length)
		XY?2=0
	On exit:
		XY?0=current EDITO value OR &80 or <&80 if BASIC V not
			present
		XY?1 Advanced BAISC ROM number
		XY?2 HIEDIT/EDIT flag (0 or 2)

	&01-&7F - Fetch overlay
	On entry:
		XY?0=3 (send length)
		XY?1=128 (receive length)
		XY?2=overlay number
	On exit:
		Overlay 1 to &7F is returned in the control block

	&80 - Convert SWI string to number
	On entry:
		XY?0=4+length of string (send length)
		XY?1=5 (receive length)
		XY?2=&80
		XY+3=CR-terminated string to match with leading "OS_"
			removed.
	On exit:
		XY!0=SWI number
		XY?4=reault, &00=matched, &FF=unknown

	&81 - Convert SWI number to string
	On entry:
		XY?0=7 (send length)
		XY?1=32 (receive length)
		XY?2=&81
		XY!3=SWI number
	On exit:
		XY+0.. unterminated SWI string, including starting "OS_"
		XY?31=string length or >&7F if unknown

	&82 - HELP
	On entry:
		XY?0=128 (send length)
		XY?1=0 (receive length)
		XY?2=&82
		XY+3..127 should contain a copy of BASIC's workspace
			from &0000 to &007C.
	On exit:
		The call outputs information to OSWRCH. The control block
		is unchanged.

	&83 - HELP <keyword>
	On entry:
		XY?0=128 (send length)
		XY?1=0 (receive length)
		XY?2=&83
		XY+3..127=CR-terminated tokenised string following HELP.
	On exit:
		The call accesses the BASHELP file and outputs information
		to OSWRCH. The control block is unchanged.

	&84 - HELP . (dot)
	On entry:
		XY?0=3 (send length)
		XY?1=0 (receive length)
		XY?2=&84
	On exit:
		Similar to &83, except no help string required, and whole
		help file is output.

	&85 - CALL or USR in I/O memory
	On entry:
		XY?0=11 (send length)
		XY?1=11 (receive length)
		XY?2=&85
		XY?3=A register
		XY?4=X register
		XY?5=Y register
		XY?6=P register (only Cy valid)
		XY!7=address
	On exit:
		XY!3=AXYP returned from called code.
	If the address if &FFrrxxxx, then ROM rr will be called, otherwise
	the current language ROM will be paged in.

	&86-&FF - reserved.

OSWORD &B5 - PRES OSWORD editor calls
-------------------------------------
	PRES products such as the File Manager and Editor issue this call so
	other ROMs can provide command options to call them.
	On entry,
		XY+0   Output control block length
		XY+1   Returned control block length
		XY+2   Command
		XY+3   Title string of ROM to issue command to, terminated with &00
		XY+x   Filename string, terminated with &00

	Commands:
	&00 - Returns available OSWORD &B5 commands at XY+2
		XY+2  Number of commands
		XY+3  Command string, &00
		XY+x  Command string, &00, etc.

	&01+ - Execute the specified command

OSWORD &B5 - PRES Advanced BASIC Editor
---------------------------------------
	On entry,
		XY+3   "BASIC Editor & Toolkit", &00
		XY+26  Filename string, terminated with &00

	Commands:
	&00 - Returns available OSWORD &B5 commands at XY+2
		XY+2  &02,"Load",&00,"Append",&00

	&01 - Enters BASIC Editor specifying filename to Load
		Inserts "L ",filename string, <cr> into keyboard
		buffer, then executes '*BE'

	&02 - Enters BASIC Editor specifying filename to Append
		Inserts "A ",filename string, <cr> into keyboard
		buffer, then executes '*BE'

OSWORD &B5 - Advanced File Manager
----------------------------------
	The PRES Advanced File Manager provides the following
	OSWORD &B5 command calls:
	    BASIC  VIEW       VIEWSHEET  VIEWSPELL  VIEWSTORE  WORDWISE     EDIT
	&01 CHAIN  LOAD       LOAD       LOAD       LOAD       LOAD         LOAD
	&02 LOAD   NEW, LOAD  LW         READ       LF         LOAD CURSOR
	&03 *TYPE  READ       PRINTER               U
	&04 *DUMP  NEW, READ                        PRINTER
	&05 *LIST  READ 1
	&06 *RUN   PRINT
	&07 *EXEC  PRINTER

&BB 187 Read/Write Morley RAMdisk				RAMdisc
	NB: Cannot be called across the Tube, and cannot transfer across
	the Tube.
	On entry:
		XY?0   = 0 for read, &80 for write
		XY?1,2 = I/O memory address
		XY?3,4 = RAMdisk start sector
		XY?5   = number of 256-byte sectors to transfer
	On exit, control block unchanged

&BB 187 Print screen dump					SCDUMP
	On entry:
		Control block contents ignored

&BE 190 Disassemble data					DISS
	This call disassembles the supplied data to create a single line of
	disassembly.
	On entry:
		XY?0=&10 (send block length)
		XY?1=&20 (receive block length)
		XY?2=cpu number
		XY?3=mask flag (usually zero)
		XY!4=address the disassembly comes from
		XY+8... contains the data to be disassembled (usually four
			bytes)
	On exit:
		XY?2=number of bytes disassembled
		XY?3=result byte
		XY+4... CR-terminated string with the disassembly in it.

	The supplied mask flag is inverted and ANDed with the result byte
	before it is returned. Some cpu codes are:
		0=reserved			38=80386
		2=6502				44=ARM
		6=80x86				48=80486
		9=6809				65=65xx series
		11=pdp11			68=68000
		12=65C12			80=Z80
		18=80186			85=8085
		28=80286			86=80x86
		30=oggin			88=8080

	The result flag contains:
		b7=unrecognised code
		b6=absolute branch, jump, return, etc., suitable place
			for a extra blank line in disassembly
		b5-b0 hold cpu-specific infomation

	If on entry, XY?0=8, then the the call returns the CPU name in a
	CR-terminated string at XY+4 onwards.

&BF 191 Fetch URI						BBCURI
	Fetches a resource specified by a Uniform Resource Indicator.
	On entry:
		XY?0=5+string length (send block length)
		XY?1=16 (receive block length)
		XY?2=command
		XY?3=0, holds returned result
		XY+4... CR-terminated URI string
	Commands include:
		1=fetch, returns file handle in XY?3 or zero if not found.

&C0 192 Transfer data between Eureka memory areas
	On entry:
		XY?0=12 (send block length)
		XY?1=12 (receive block length)
		XY?2=&FE
		XY?3=&FF
		XY?4=&0B Command=data transfer
		XY?5=subcommand 1=read, 2=write, 3=copy
		XY?6..7  =source start address
		XY?8..9  =source end address
		XY?10..11=destination start address

&C8 200 Pass SWI Operation to Host				JGH
	This call passes a SWI to the host to be executed. Values passed
	can be translated to and from absolute ARM address by setting bits
	in the translate bytes.
	On entry:
		XY?0 =regs*4+8 (send block length)
		XY?1 =regs*4+8 (the receive block length)
		XY?2 =bitmap of outgoing register values to translate
			to ARM absolute addresses, b0=1 - r0, b1=1 - r1, etc.,
		XY?3 =bitmap of incoming register values to translate back
			to local processor addresses as with XY?2
		XY!4 =SWI number
		XY!8 =r0 value
		XY!12=r1 value
		... continues onwards up to the number specified by XY?0
		and XY?1.
	On exit:
		XY!4=b0-b3=returned flags, NZCV. [*]
	If V set in b0, an error number is returned in XY!4 and the
	CR-terminated error string returned in XY+8 onwards.

&FA 250 Data transfer over Tube 				80x86 Tube OS
	On entry:
		XY?0     =&0D or &0E (send block length)
		XY?1     =&10 (receive block length)
		XY!5     =I/O processor address
		XY+6..7  =80x86 offset address
		XY+8..9  =80x86 segment address
		XY+10..11=data length
		XY?12    =function
		XY?13    =memory access control if XY?0=&0E.

	The functions are the same as the Tube values:
		0 - write to I/O as single bytes
		1 - read from I/O as single bytes
		2 - write to I/O as byte pairs
		3 - read from I/O as byte pairs
		6 - write to I/O as groups of 256 bytes
		7 - read from I/O as groups of 256 bytes

	If the memory access control byte is used, its format is:
		b0-b3=ROM number
		b4   =0 use specified ROM, b4=1 use current ROM
		b5   =0 use main memory, b5=1 use screen memory
		b6   =1 ignore b5 and use shadow memory
		b7   unused.

&FB 251 WD1770/2 Floppy Disk Control				80x86 DOS
	The control block is ignored, so for speed, set XY?0=0 and XY?1=0.
	Commands are sent from the 80x86 via Tube register 2. These are:
	0 - Finish
	1 - Master FDC command; register 2 sends 4-byte address low to
	    high, R/W command, Write flag, Interrupt mask, number of
	    sectors, FDC command.
	2 - BBC B/B+ command; as for command 1.
	3 - Claim Tube and NMI.
	4 - Release Tube and NMI.
	5..&FF - Write byte sent though register2 to &FExx.

&FC 252 DOS CRTC Control					80x86 DOS
	The control block is ignored, so for speed, set XY?0=0 and XY?1=0.
	Commands are sent from the 80x86 via Tube register 2:
	b7=0 - program CRTC, command specifies register, next byte sent
	    through register 2 is the CRTC data.
	&FC - write to mouse port (does nothing)
	&FD - intercept events
	&FE - initialise mouse driver
	&FF - finish. All other commands finish the transaction.

&FD 253 -

&FE 254 DOS Text output (unimplemented) 			80x86 DOS
	Just returns

&FE 254 Z80 SP Disc Read					Z80 CP/M

&FF 255 DOS fast screen control 				80x86 DOS
	The control block is ignored, so for speed, set XY?0=0 and XY?1=0.
	Commands are sent from the 80x86 via Tube register 2, first, the
	address is sent, high byte then low byte. This address is updated
	for the data sent and wraps round from &7FFF to &4000. If the high
	byte is &00, no low byte is sent, and the routine finishes. Then
	the command loop is entered. The command is sent through register
	2:

	&FF - single byte read through register 1 fills the following eight
	    bytes of screen memory.
	&00 - eight bytes read though register 1 fill following eight bytes
	    of screen memory.
	Other - loop back to wait for address or termination.

&FF 255 Z80 Data transfer over Tube				Z80 Tube OS
	On entry:
		XY?0     =&0D (send block length)
		XY?1     =&01 (receive block length)
		XY!2     =I/O address
		XY!6     =Z80 address
		XY+10..11=data length
		XY?12    =command, 0=read from I/O, 1=write to I/O.

------------------------------------------------------------------------------
        
ADFS      = Advanced Disc Filing System, Acorn
AdvBASIC  = Advanced BASIC (BASIC V)
AMX       = AMX Super Art ROM, Elliot Software for AMS
Spring    = Springboard ARM development system
DISS      = Disassembly routines, JGH
DFS       = Disc Filing System 0.90/1.20, Acorn
DVR       = 6502 Development ROM, AJCD
BBCURI    = BBC URI Fetcher, JGH
HADFS     = Harston Advance Disk Filing System, JGH
HDFS      = Hierarchical DFS, AJCD
HKSET     = Hong Kong Stock Exchange Terminal
MOS       = Machine Operating System 1.20, Acorn
NFS       = Network Filing System 3.34, Acorn
SPROW     = Robert Sprowson Systems
TQCOM     = Tequilacomm, D.A.Sainty
TubeLink  = TubeLink, Colin Dean
GoMMC     = GoMMC memory card, John Kortink
CDFS      = Cumana Electron DFS

Update History
--------------
21-Jun-1993: Angus Duggan, initial list of &00-&0F, &4E..&5E, &7D..&7F.
28-Feb-1997: J.G.Harston, Re-edited, added &10-&16, &20, &42, &43, &45,
	&5A, &60, &62-&64, &70-&73, &7A, &7B, &BE, &FA, &FE, &FF.
04-Oct-1998: J.G.Harston, updated &20, added &51, &89, &8A, &C8, &FB-&FD.
15-May-1999: J.G.Harston, added &47, updated &7D.
03-Oct-2001: J.G.Harston, added &BF.
30-Aug-2003: J.G.Harston, added &20, &21, &45.
07-Aug-2004: J.G.Harston, added &80, &81, &85, &86.
30-Aug-2004: J.G.Harston, added &B0.
24-Sep-2006: J.G.Harston, added &13/11-17, &B2.
12-Jun-2007: J.G.Harston, added details of &B2, reformatted text.
27-Feb-2008: J.G.Harston, added &BB, &50, &51, &72, &80 IEEE.
14-Nov-2010: J.G.Harston, added &BB SCDUMP.
12-Jul-2012: J.G.Harston, details of &5F ISMEC Monitor, &51 HKSET.
20-Oct-2015: J.G.Harston, details of &28-&32 PRISMA calls.
10-Apr-2017: J.G.Harston, details of &49 Integra-B Windows calls.
18-Dec-2015: J.G.Harston, added &C0 Eureka call, &B5 PRES call.
&22,&23 UtilRAM calls.