Jon Relay's Apple II Info Archives

Screen Holes

n is the slot number a peripheral card is in.

Apple II

$0478    1144    Slot address of card using $C800 space
                 //c mouse: clamping minimum, lo byte
$04F8    1272    //c mouse: clamping maximum, lo byte
$0578    1400    //c mouse: clamping minimum, hi byte
$05F8    1528    //c mouse: clamping maximum, hi byte

Super Serial Card

$0478+n  1144+n  Delay: b0-1=FF b2-3=LF b4-5=CR b6-7=translate option
$04F8+n  1272+n  Accumulator for firmware's command processor
$0578+n  1400+n  b0-2=cmd mode b3-5=slot to ch to b6=lc b7=terminal/CR
$05F8+n  1528+n  b0-6=command byte b7=zap control commands
$0678+n  1656+n  Error: b0=parity b1=framing b2=overrun b3=carrier b5=error
$06F8+n  1784+n  Modem Mode: b0-2=screen slot b3-7=$Cs00 space entry point
                 Printer Mode: current printer width
$0778+n  1912+n  Modem Mode: input buffer
                 Printer Mode: current column
$07F8+n  2040+n  b0=auto LF b1=comm.mode b2=keyb inp b3=chk XOFF b4=Pascal
                 b5=ignore LF b6=enable lc/tabs b7=echo

Apple IIc Serial

$0578+n  1400+n  printer width
$05F8+n  1528+n  scratch
$0678+n  1656+n  b7=parsing command string
$06F8+n  1784+n  current command character
$0778+n  1912+n  b6=auto LF b7=echo
$07F8+n  2040+n  current printer column

80-Column Card

$0478+n  1144+n  address of last output routine used by firmware
$04F8+n  1272+n  video firmware operating mode
$0578+n  1400+n  horizontal cursor position
$05F8+n  1528+n  vertical cursor position
$0678+n  1656+n  character to be printed/read
$06F8+n  1784+n  Pascal GOTOXY X coordinate
$0778+n  1912+n  scratch
$07F8+n  2040+n  scratch

Mouse Card

$0478+n  1144+n  X coordinate, lo byte
$04F8+n  1272+n  Y coordinate, lo byte
$0578+n  1400+n  X coordinate, hi byte
$05F8+n  1528+n  Y coordinate, hi byte
$0778+n  1912+n  status: b1=movement int b2=button int b3=VBL int
                 b5=movement b6=still down from last b7=button down
$07F8+n  2040+n  mode: b0=active b1=VBL on move b2=VBL on button b3=VBL

Apple IIc Auxiliary Memory

$0478    1144    printer port ACIA control reg
$0479    1145    printer port ACIA command reg
$047A    1146    printer port flags: b0=comm b6=auto LF b7=echo
$047B    1147    printer port printer width
$047C    1148    modem port ACIA control reg
$047D    1149    modem port ACIA command reg
$047E    1150    modem port flags: b0=comm b6=auto LF b7=echo
$047F    1151    modem port line length

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