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Updated the 5170 BIOS map, updated 8042 info, fixed some 8042 controller commands, made HLT work, and fixed the debugger's history buffer when executing a mix of real-mode and protected-mode instructions

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Jeff Parsons 2014-10-01 17:33:17 -07:00 • committed by jeffpar
commit 93b81c47b7
13 changed files with 804 additions and 287 deletions
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35
my_modules/pcjs-client/lib/x86opxx.js
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@ -3192,45 +3192,34 @@ var X86OpXX = {
* @this {X86CPU}
*
* op=0xF4 (hlt)
*
* WARNING: Because other components "thrive" on the CPU's runCPU() loop notifications,
* (eg, the Video component's blinking elements, and the Chipset component's timers),
* we can't really stop. What we do instead is set INTFLAG.HALT and "wait" for INTFLAG.INTR
* to be set; since stepCPU() is already monitoring intFlags, this INTFLAG.HALT bit doesn't
* impact performance.
*
* All stepCPU() has to do when INTFLAG.HALT is set is advance the cycle count without
* advancing the program counter. That continues indefinitely until stepCPU() finally detects
* and acknowledges a INTFLAG.INTR notification, at which point INTFLAG.HALT is cleared.
*/
opHLT: function() {
/*
* The CPU is never REALLY halted by a HLT instruction; instead, by setting X86.INTFLAG.HALT,
* we are signalling to stepCPU() that it's free to end the current burst AND that it should not
* execute any more instructions until checkINTR() indicates a hardware interrupt is requested.
*/
this.intFlags |= X86.INTFLAG.HALT;
this.nStepCycles -= 2;
/*
* We halt the machine only if a Debugger is present AND Debugger checks are enabled (eg,
* one or more breakpoints are set, or the global DEBUG flag is set, etc), on the theory that
* whoever's using the Debugger might like to see halts; we also halt the machine if interrupts
* have been disabled, since that means it's dead in the water (we have no NMI generation
* mechanism at the moment).
*
* Otherwise, HLT is treated like any other instruction.
* If a Debugger is present AND Debugger checks are enabled (eg, one or more breakpoints are set,
* or the global DEBUG flag is set, etc), then we REALLY halt the CPU, on the theory that whoever's
* using the Debugger would like to see HLTs.
*/
if (DEBUGGER && this.dbg && this.dbg.checksEnabled(true)) {
this.advanceIP(-1); // this is purely for the Debugger's benefit, to show the HLT
this.haltCPU();
return;
}
/*
* We also REALLY halt the machine if interrupts have been disabled, since that means it's dead
* in the water (we have no NMI generation mechanism at the moment).
*/
if (!this.getIF()) {
if (DEBUGGER && this.dbg) this.advanceIP(-1);
this.haltCPU();
// return;
}
/*
* Per my discussion of waitCPU() in cpu.js, this seems rather pointless, so I don't call it anymore.
* If you re-enable this, make sure you re-enable the return statement above, too.
*
this.waitCPU();
*/
},
/**
* @this {X86CPU}