Prisma display

1536x1148x16 colours or
 768x1148x256 colours

1536x1148 (&600 x &47C, 96x71.75)

Extendable to
3072x2730 (&C00 x &AAA, 192x170)


VDU 23,19
VDU 23,20 - defines area of 'Upper Screen'
up to 568px high
VDU 23,21 - defines area of 'Lower Screen'
up to 568px high
VDU 23,22/23/24 - defines area of 'Overlay Screen'

COLOUR 0-127 - select foreground text colour 0-127
COLOUR 128-255 - select background text colour 0-127
GCOL 0,0-255 - select graphics colour 0-255

GCOL 0 - set
1 OR
2 AND
3 XOR
4 invert
5 no change
6 undefined
7 define colour comparison colour
8 plot if already set to comparison colour
9 plot if not already set to comparison colour
10 plot if < than plot colour
11 plot if >= than plot colour
+16 = foreground, eg GCOL 16+n,col - sets foreground to 0-255
+32 = background, eg GCOL 32+n,col - sets background to 0-255

GCOL m,col col=0-127 foreground=0-127
col=128-255 background=128-255

PLOT 185 move area
PLOT 186 copy area
PLOT 187 copy area, ignoring previous cursor positions

VDU 19,l,p,0,0,0 - use physical nonflashing colour
VDU 19,l,p,>0,>0,>0 - use colour components

VDU 23,6  define dotted line
VDU 23,19 define roller screen
VDU 23,20,xmin;ymin;xmax;ymax; define upper screen (xmax fixed at xmin+1662)
VDU 23,21,xmin;ymin;xmax;ymax; define lower screen (xmax fixed at xmin+1662)
VDU 23,22,xmin;ymin;xmax;ymax; define overlay window, waits for VDU 23,24
VDU 23,23,xmin;ymin;xmax;ymax; define overlay window, used immediately
VDU 23,24,xmin;ymin;0;0;       define overlay window
VDU 23,25,xmin;ymin;xmax;ymax; define movement limits
VDU 23,28,xmin;ymin;xmax;ymax; define clipping region

*FX13,32 - disable Prisma video field event
*FX14,32 - enable Prisma video field event

&FCBx Prisma Graphics Processor