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Tweaks to PIT latch operation - Juko XT now boots again.

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This commit is contained in:
TomW 2015-09-15 21:53:45 +01:00
commit 6b82be0624
2 changed files with 7 additions and 2 deletions
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1
src/ibm.h
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@ -213,6 +213,7 @@ typedef struct PIT
int count[3]; int count[3];
int using_timer[3]; int using_timer[3];
int initial[3]; int initial[3];
int latched[3];
} PIT; } PIT;
PIT pit; PIT pit;

8
src/pit.c
View file

@ -336,6 +336,7 @@ void pit_write(uint16_t addr, uint8_t val, void *priv)
pit.ctrl |= 0x30; pit.ctrl |= 0x30;
pit.rereadlatch[t] = 0; pit.rereadlatch[t] = 0;
pit.rm[t] = 3; pit.rm[t] = 3;
pit.latched[t] = 1;
} }
else else
{ {
@ -348,7 +349,7 @@ void pit_write(uint16_t addr, uint8_t val, void *priv)
pit.rm[val>>6]=3; pit.rm[val>>6]=3;
pit.rl[t] = pit_read_timer(t); pit.rl[t] = pit_read_timer(t);
} }
// pit.rereadlatch[val>>6]=1; pit.rereadlatch[val>>6]=1;
if ((val>>6)==2) ppispeakon=speakon=(pit.m[2]==0)?0:1; if ((val>>6)==2) ppispeakon=speakon=(pit.m[2]==0)?0:1;
pit.initial[t] = 1; pit.initial[t] = 1;
if (!pit.m[val >> 6]) if (!pit.m[val >> 6])
@ -421,7 +422,7 @@ uint8_t pit_read(uint16_t addr, void *priv)
{ {
case 0: case 1: case 2: /*Timers*/ case 0: case 1: case 2: /*Timers*/
t = addr & 3; t = addr & 3;
if (pit.rereadlatch[addr & 3]) if (pit.rereadlatch[addr & 3] && !pit.latched[addr & 3])
{ {
pit.rereadlatch[addr & 3] = 0; pit.rereadlatch[addr & 3] = 0;
pit.rl[t] = pit_read_timer(t); pit.rl[t] = pit_read_timer(t);
@ -431,14 +432,17 @@ uint8_t pit_read(uint16_t addr, void *priv)
case 0: case 0:
temp = pit.rl[addr & 3] >> 8; temp = pit.rl[addr & 3] >> 8;
pit.rm[addr & 3] = 3; pit.rm[addr & 3] = 3;
pit.latched[addr & 3] = 0;
pit.rereadlatch[addr & 3] = 1; pit.rereadlatch[addr & 3] = 1;
break; break;
case 1: case 1:
temp = (pit.rl[addr & 3]) & 0xFF; temp = (pit.rl[addr & 3]) & 0xFF;
pit.latched[addr & 3] = 0;
pit.rereadlatch[addr & 3] = 1; pit.rereadlatch[addr & 3] = 1;
break; break;
case 2: case 2:
temp = (pit.rl[addr & 3]) >> 8; temp = (pit.rl[addr & 3]) >> 8;
pit.latched[addr & 3] = 0;
pit.rereadlatch[addr & 3] = 1; pit.rereadlatch[addr & 3] = 1;
break; break;
case 3: case 3: