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Added scaffolding for PC8080 SerialPort

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This commit is contained in:
Jeff Parsons 2016-08-08 15:25:57 -07:00
commit d31bfb0e6e
11 changed files with 1075 additions and 445 deletions
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31
modules/pc8080/lib/video.js
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@ -1064,19 +1064,26 @@ Video.prototype.updateScreen = function(n)
if (n >= 0) {
if (this.rateInterrupt) {
if (!(n & 1)) {
/*
* On even updates, call cpu.requestINTR(1), and also update our copy of the screen.
*/
this.cpu.requestINTR(1);
/*
* TODO: Incorporate these hard-coded interrupt vector numbers into configuration blocks.
*/
if (this.rateInterrupt == 120) {
if (!(n & 1)) {
/*
* On even updates, call cpu.requestINTR(1), and also update our copy of the screen.
*/
this.cpu.requestINTR(1);
} else {
/*
* On odd updates, call cpu.requestINTR(2), but do NOT update our copy of the screen, because
* the machine has presumably only updated the top half of the frame buffer at this point; it will
* update the bottom half of the frame buffer after acknowledging this interrupt.
*/
this.cpu.requestINTR(2);
fUpdate = false;
}
} else {
/*
* On odd updates, call cpu.requestINTR(2), but do NOT update our copy of the screen, because
* the machine has presumably only updated the top half of the frame buffer at this point; it will
* update the bottom half of the frame buffer after acknowledging this interrupt.
*/
this.cpu.requestINTR(2);
fUpdate = false;
this.cpu.requestINTR(4);
}
}