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Added PIC auto-EOI mode - Crystal Dream now runs

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This commit is contained in:
SarahW 2016-05-03 21:27:35 +01:00
commit 57e2a4d678
2 changed files with 53 additions and 1 deletions
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2
src/ibm.h
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@ -267,7 +267,7 @@ extern int key_inhibit;
/*PIC*/
typedef struct PIC
{
uint8_t icw1,mask,ins,pend,mask2;
uint8_t icw1,icw4,mask,ins,pend,mask2;
int icw;
uint8_t vector;
int read;

52
src/pic.c
View file

@ -50,6 +50,26 @@ void pic_update_mask(uint8_t *mask, uint8_t ins)
}
}
static void pic_autoeoi()
{
int c;
for (c=0;c<8;c++)
{
if (pic.ins&(1<<c))
{
pic.ins&=~(1<<c);
pic_update_mask(&pic.mask2, pic.ins);
if (c == 2 && (pic2.pend&~pic2.mask)&~pic2.mask2)
pic.pend |= (1 << 2);
pic_updatepending();
return;
}
}
}
void pic_write(uint16_t addr, uint8_t val, void *priv)
{
int c;
@ -75,6 +95,8 @@ void pic_write(uint16_t addr, uint8_t val, void *priv)
else pic.icw=0;
break;
case 3: /*ICW4*/
pic.icw4 = val;
// pclog("ICW4 = %02x\n", val);
pic.icw=0;
break;
}
@ -150,6 +172,23 @@ void pic_init()
io_sethandler(0x0020, 0x0002, pic_read, NULL, NULL, pic_write, NULL, NULL, NULL);
}
static void pic2_autoeoi()
{
int c;
for (c = 0; c < 8; c++)
{
if (pic2.ins & (1 << c))
{
pic2.ins &= ~(1 << c);
pic_update_mask(&pic2.mask2, pic2.ins);
pic_updatepending();
return;
}
}
}
void pic2_write(uint16_t addr, uint8_t val, void *priv)
{
int c;
@ -174,6 +213,7 @@ void pic2_write(uint16_t addr, uint8_t val, void *priv)
else pic2.icw=0;
break;
case 3: /*ICW4*/
pic2.icw4 = val;
pic2.icw=0;
break;
}
@ -326,6 +366,10 @@ uint8_t picinterrupt()
pic.ins |= (1 << c);
pic_update_mask(&pic.mask2, pic.ins);
pic_updatepending();
if (pic.icw4 & 0x02)
pic_autoeoi();
return c+pic.vector;
}
}
@ -345,6 +389,10 @@ uint8_t picinterrupt()
pic_update_mask(&pic.mask2, pic.ins);
pic_updatepending();
if (pic2.icw4 & 0x02)
pic2_autoeoi();
return c+pic2.vector;
}
}
@ -357,6 +405,10 @@ uint8_t picinterrupt()
pic.ins |= (1 << c);
pic_update_mask(&pic.mask2, pic.ins);
pic_updatepending();
if (pic.icw4 & 0x02)
pic_autoeoi();
return c+pic.vector;
}
}