Skip to content

Commit

Permalink
Fixes: i8271 emulation always reports drive as ready (stardot#20)
Browse files Browse the repository at this point in the history
  • Loading branch information
@hoglet67
hoglet67 committed Mar 8, 2017
1 parent 8098999 commit 9798bd8
Showing 1 changed file with 25 additions and 13 deletions.
38 changes: 25 additions & 13 deletions src/i8271.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -22,10 +22,15 @@ int i8271_getdata(int last);
int byte;
int i8271_verify = 0;

// Output Port bit definitions in i8271.drvout
#define SIDESEL 0x20
#define DRIVESEL0 0x40
#define DRIVESEL1 0x80
#define DRIVESEL (DRIVESEL0 | DRIVESEL1)

struct
{
uint8_t command, params[5];
int drivesel;
int paramnum, paramreq;
uint8_t status;
uint8_t result;
Expand All @@ -35,7 +40,7 @@ struct
uint8_t data;
int phase;
int written;

uint8_t drvout;
} i8271;

Expand Down Expand Up @@ -83,6 +88,7 @@ void i8271_spinup()
void i8271_spindown()
{
motoron = 0;
i8271.drvout &= ~DRIVESEL;
}

void i8271_setspindown()
Expand Down Expand Up @@ -153,7 +159,13 @@ void i8271_write(uint16_t addr, uint8_t val)
i8271.command = val & 0x3F;
if (i8271.command == 0x17) i8271.command = 0x13;
// printf("8271 command %02X!\n",i8271.command);
i8271.drivesel = val >> 6;
// Only commands < ReadDriveStatus actually change the drive select signals
// We use this later to generate RDY in the ReadDriveStatus command
if (i8271.command < 0x2C)
{
i8271.drvout &= ~DRIVESEL;
i8271.drvout |= val & DRIVESEL;
}
curdrive = (val & 0x80) ? 1 : 0;
i8271.paramnum = 0;
i8271.paramreq = i8271_getparams();
Expand All @@ -165,8 +177,8 @@ void i8271_write(uint16_t addr, uint8_t val)
case 0x2C: /*Read drive status*/
i8271.status = 0x10;
i8271.result = 0x80 | 8 | track0;
if (i8271.drivesel & 1) i8271.result |= 0x04;
if (i8271.drivesel & 2) i8271.result |= 0x40;
if (i8271.drvout & DRIVESEL0) i8271.result |= 0x04;
if (i8271.drvout & DRIVESEL1) i8271.result |= 0x40;
// printf("Status %02X\n",i8271.result);
break;

Expand Down Expand Up @@ -314,7 +326,7 @@ void i8271_callback()
if (!i8271.phase)
{
i8271.curtrack[curdrive] = i8271.params[0];
disc_writesector(curdrive, i8271.cursector, i8271.params[0], (i8271.drvout & 0x20) ? 1 : 0, 0);
disc_writesector(curdrive, i8271.cursector, i8271.params[0], (i8271.drvout & SIDESEL) ? 1 : 0, 0);
i8271.phase = 1;

i8271.status = 0x8C;
Expand All @@ -333,7 +345,7 @@ void i8271_callback()
return;
}
i8271.cursector++;
disc_writesector(curdrive, i8271.cursector, i8271.params[0], (i8271.drvout & 0x20) ? 1 : 0, 0);
disc_writesector(curdrive, i8271.cursector, i8271.params[0], (i8271.drvout & SIDESEL) ? 1 : 0, 0);
byte = 0;
i8271.status = 0x8C;
i8271.result = 0;
Expand All @@ -349,7 +361,7 @@ void i8271_callback()
// i8271.realtrack+=diff;
// disc_seek(0,i8271.realtrack);
// printf("Re-seeking - track now %i %i\n",i8271.curtrack,i8271.realtrack);
disc_readsector(curdrive, i8271.cursector, i8271.params[0], (i8271.drvout & 0x20) ? 1 : 0, 0);
disc_readsector(curdrive, i8271.cursector, i8271.params[0], (i8271.drvout & SIDESEL) ? 1 : 0, 0);
i8271.phase = 1;
return;
}
Expand All @@ -364,7 +376,7 @@ void i8271_callback()
return;
}
i8271.cursector++;
disc_readsector(curdrive, i8271.cursector, i8271.params[0], (i8271.drvout & 0x20) ? 1 : 0, 0);
disc_readsector(curdrive, i8271.cursector, i8271.params[0], (i8271.drvout & SIDESEL) ? 1 : 0, 0);
byte = 0;
break;

Expand All @@ -375,7 +387,7 @@ void i8271_callback()
i8271.curtrack[curdrive] = i8271.params[0];
// i8271.realtrack+=diff;
// disc_seek(0,i8271.realtrack);
disc_readaddress(curdrive, i8271.params[0], (i8271.drvout & 0x20) ? 1 : 0, 0);
disc_readaddress(curdrive, i8271.params[0], (i8271.drvout & SIDESEL) ? 1 : 0, 0);
i8271.phase = 1;
return;
}
Expand All @@ -391,15 +403,15 @@ void i8271_callback()
return;
}
i8271.cursector++;
disc_readaddress(curdrive, i8271.params[0], (i8271.drvout & 0x20) ? 1 : 0, 0);
disc_readaddress(curdrive, i8271.params[0], (i8271.drvout & SIDESEL) ? 1 : 0, 0);
byte = 0;
break;

case 0x23: /*Format*/
if (!i8271.phase)
{
i8271.curtrack[curdrive] = i8271.params[0];
disc_writesector(curdrive, i8271.cursector, i8271.params[0], (i8271.drvout & 0x20) ? 1 : 0, 0);
disc_writesector(curdrive, i8271.cursector, i8271.params[0], (i8271.drvout & SIDESEL) ? 1 : 0, 0);
i8271.phase = 1;

i8271.status = 0x8C;
Expand All @@ -416,7 +428,7 @@ void i8271_callback()
i8271_verify=0;
return;
}
disc_format(curdrive, i8271.params[0], (i8271.drvout & 0x20) ? 1 : 0, 0);
disc_format(curdrive, i8271.params[0], (i8271.drvout & SIDESEL) ? 1 : 0, 0);
i8271.phase = 2;
break;

Expand Down

0 comments on commit 9798bd8

Please sign in to comment.