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Timer: Write BIOS data area at a time that follows the BIOS zeroing the lower 32KB on first boot, so that the 8/10MHz timer clock source bit can be reflected properly

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This commit is contained in:
Jonathan Campbell 2018-02-15 21:34:31 -08:00
parent cc913aed9c
commit 24789fe685
1 changed files with 7 additions and 5 deletions
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12
src/hardware/timer.cpp
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@ -512,6 +512,13 @@ void TIMER_BIOS_INIT_Configure() {
PCSPEAKER_SetCounter(pit[pcspeaker_pit].cntr,pit[pcspeaker_pit].mode);
PIC_AddEvent(PIT0_Event,pit[0].delay);
if (IS_PC98_ARCH) {
/* BIOS data area at 0x501 tells the DOS application which clock rate to use */
phys_writeb(0x501,
((PIT_TICK_RATE == PIT_TICK_RATE_PC98_8MHZ) ? 0x80 : 0x00) /* bit 7: 1=8MHz 0=5MHz/10MHz */
);
}
}
void TIMER_OnPowerOn(Section*) {
@ -617,11 +624,6 @@ void TIMER_OnEnterPC98_Phase2(Section*) {
ReadHandler[1].Install(IS_PC98_ARCH ? 0x73 : 0x41,read_latch,IO_MB);
ReadHandler[2].Install(IS_PC98_ARCH ? 0x75 : 0x42,read_latch,IO_MB);
/* BIOS data area at 0x501 tells the DOS application which clock rate to use */
phys_writeb(0x501,
((PIT_TICK_RATE == PIT_TICK_RATE_PC98_8MHZ) ? 0x80 : 0x00) /* bit 7: 1=8MHz 0=5MHz/10MHz */
);
latched_timerstatus_locked=false;
gate2 = false;