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Smoothed out PCx86 dynamic CPU speed recalculation by no longer truncating the current cycle multiplier

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Jeff Parsons 2017-08-08 19:25:08 -07:00 • committed by Jeff Parsons
commit 7f973a03b9
23 changed files with 1351 additions and 1308 deletions
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29
modules/pcx86/lib/cpu.js
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@ -570,7 +570,7 @@ class CPU extends Component {
*/
calcCycles()
{
var nMultiplier = (this.counts.mhzCurrent / this.counts.mhzBase)|0;
var nMultiplier = this.counts.mhzCurrent / this.counts.mhzBase;
if (!nMultiplier || nMultiplier > this.counts.nTargetMultiplier) nMultiplier = this.counts.nTargetMultiplier;
this.counts.msPerYield = Math.round(1000 / CPU.YIELDS_PER_SECOND);
this.counts.nCyclesPerYield = Math.floor(this.counts.nBaseCyclesPerSecond / CPU.YIELDS_PER_SECOND * nMultiplier);
@ -713,9 +713,9 @@ class CPU extends Component {
var fSuccess = true;
if (nMultiplier !== undefined) {
/*
* If we haven't reached 80% (0.8) of the current target speed, revert to the default multiplier.
* If we haven't reached 90% (0.9) of the current target speed, revert to the default multiplier.
*/
if (this.counts.mhzCurrent > 0 && this.counts.mhzCurrent / this.counts.mhzTarget < 0.8) {
if (this.counts.mhzCurrent > 0 && this.counts.mhzCurrent < this.counts.mhzTarget * 0.9) {
nMultiplier = this.counts.nBaseMultiplier;
fSuccess = false;
}
@ -855,7 +855,7 @@ class CPU extends Component {
this.calcSpeed(nCycles, msElapsed);
if (msRemainsThisRun < 0 || this.counts.mhzCurrent < this.counts.mhzTarget) {
if (msRemainsThisRun < 0) {
/*
* Try "throwing out" the effects of large anomalies, by moving the overall run start time up;
* ordinarily, this should only happen when the someone is using an external Debugger or some other
@ -866,14 +866,17 @@ class CPU extends Component {
}
/*
* If the last burst took MORE time than we allotted (ie, it's taking more than 1 second to simulate
* nCyclesActual), all we can do is yield for as little time as possible (ie, 0ms) and hope that the
* simulation is at least usable.
* nBaseCyclesPerSecond), all we can do is yield for as little time as possible (ie, 0ms) and hope
* that the simulation is at least usable.
*/
msRemainsThisRun = 0;
}
else if (this.counts.mhzCurrent < this.counts.mhzTarget) {
msRemainsThisRun = 0;
}
if (DEBUG && this.messageEnabled(Messages.LOG) && msRemainsThisRun) {
this.log("calcRemainingTime: " + msRemainsThisRun + "ms to sleep after " + this.counts.msEndThisRun + "ms");
if (DEBUG && this.messageEnabled(Messages.CPU)) {
this.printMessage("calcRemainingTime: sleep " + msRemainsThisRun + "ms after " + (this.counts.msEndThisRun - this.counts.msStartThisRun) + "ms burst");
}
this.counts.msEndThisRun += msRemainsThisRun;
@ -1102,9 +1105,17 @@ class CPU extends Component {
if (timer[1] < 0) continue;
timer[1] -= nCycles;
if (timer[1] <= 0) {
if (DEBUG && this.messageEnabled(Messages.CPU)) {
this.printMessage("updateTimer(" + nCycles + "): firing " + timer[0] + " with only " + (timer[1] + nCycles) + " cycles left");
}
timer[1] = -1; // zero is technically an "active" value, so ensure the timer is dormant now
timer[3](); // safe to invoke the callback function now
if (timer[2] >= 0) this.setTimer(iTimer, timer[2]);
if (timer[2] >= 0) {
this.setTimer(iTimer, timer[2]);
if (DEBUG && this.messageEnabled(Messages.CPU)) {
this.printMessage("updateTimer(" + nCycles + "): rearming " + timer[0] + " for " + timer[2] + "ms (" + timer[1] + " cycles)");
}
}
}
}
}