Date   : Sat, 05 Dec 2009 01:45:16 +0100
From   : kortink@... (John Kortink)
Subject: Tube - I/O processor memory questions

On 04 Dec 2009 23:54:51 +0000, jgh@... (Jonathan Graham
Harston) wrote:

>> Message-ID: <qnigh5hurgk9pmobqt5slt2a3d9ta2oe61@...>
> 
>John Kortink wrote:
>> Not least because it would be pretty silly to require
>> applications to have a ROM header.
> 
>No, it would be pretty silly to not require an application to have
>a ROM header, mainly, and importantly, so the Tube Client MOS can
>tell what CPU it was targetted at.
> 
>Rick Murray wrote:
>> Can anybody point to code that would provide a definitive answer?
> 
>.osCLI_IO
>LDA #&02:JSR SendR2        :\ Send command &02 - OSCLI
>JSR SendStringF8           :\ Send command string at &F8/9
>.osCLI_Ack
>JSR WaitR2                 :\ Wait for acknowledgement
>CMP #&80:BEQ LFA5C         :\ Jump if code to be entered
>PLA:RTS                    :\ Restore A and return
> 
>\ *GO - call machine code
>\ -----------------------
>.CmdGO
>AND #&DF                   :\ Ignore case
>CMP #ASC"O":BNE osCLI_IO   :\ Not '*GO', jump to pass to Tube
>JSR SkipSpaces1            :\ Move past any spaces
>JSR ScanHex:JSR SkipSpaces :\ Read hex value and move past spaces
>CMP #&0D:BNE osCLI_IO      :\ More parameters, pass to Tube to deal with
>TXA:BEQ LFA5C              :\ If no address given, jump to current program
>LDA &F0:STA &F6            :\ Set program start to address read
>LDA &F1:STA &F7
> 
>.LFA5C
>LDA &EF:PHA:LDA &EE:PHA    :\ Save current program
>JSR EnterCode
>PLA:STA &EE:STA &F2        :\ Restore current program and
>PLA:STA &EF:STA &F3        :\ set address top of memory to it
>PLA:RTS                    :\ Return to caller

Exactly. Any executable that doesn't return
when entered becomes the CAO. There's no
requirement whatsoever for a ROM header.


John Kortink

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