Fixes for reading latched values with ports 0x40-0x43.
diff --git a/msdos/ioports.c b/msdos/ioports.c
index a965d02..d72651d 100644
--- a/msdos/ioports.c
+++ b/msdos/ioports.c
@@ -26,14 +26,18 @@
DEFAULT_DEBUG_CHANNEL(int)
-static WORD tmr_8253_countmax[3] = {0xffff, 0x12, 1}; /* [2] needs to be 1 ! */
-/* if byte_toggle is TRUE, then hi byte has already been written */
-static BOOL16 tmr_8253_byte_toggle[3] = {FALSE, FALSE, FALSE};
-static WORD tmr_8253_latch[3] = {0, 0, 0};
-
-/* 4th contents are dummy */
-static BOOL16 tmr_8253_latched[4] = {FALSE, FALSE, FALSE, FALSE};
-static BYTE tmr_8253_ctrlbyte_ch[4] = {0x06, 0x44, 0x86, 0};
+static struct {
+ WORD countmax;
+ BOOL16 byte_toggle; /* if TRUE, then hi byte has already been written */
+ WORD latch;
+ BOOL16 latched;
+ BYTE ctrlbyte_ch;
+ WORD oldval;
+} tmr_8253[3] = {
+ {0xFFFF, FALSE, 0, FALSE, 0x06, 0},
+ {0x0012, FALSE, 0, FALSE, 0x44, 0},
+ {0x0001, FALSE, 0, FALSE, 0x86, 0},
+};
static int dummy_ctr = 0;
@@ -275,54 +279,53 @@
switch (port)
{
- case 0x3ba:
- case 0x3da:
- res = (DWORD)VGA_ioport_in( port );
- break;
case 0x40:
case 0x41:
case 0x42:
{
BYTE chan = port & 3;
WORD tempval = 0;
+ if (tmr_8253[chan].latched)
+ tempval = tmr_8253[chan].latch;
+ else
+ {
+ dummy_ctr -= 1 + (int)(10.0 * rand() / (RAND_MAX + 1.0));
+ if (chan == 0) /* System timer counter divisor */
+ {
+ /* FIXME: DOSVM_GetTimer() returns quite rigid values */
+ tempval = dummy_ctr + (WORD)DOSVM_GetTimer();
+ }
+ else
+ {
+ /* FIXME: intelligent hardware timer emulation needed */
+ tempval = dummy_ctr;
+ }
+ }
- if (tmr_8253_latched[chan] == TRUE)
+ switch ((tmr_8253[chan].ctrlbyte_ch & 0x30) >> 4)
{
- tempval = tmr_8253_latch[chan];
- tmr_8253_latched[chan] = FALSE;
- }
- else
- {
- dummy_ctr -= 1+(int) (10.0*rand()/(RAND_MAX+1.0));
- if (chan == 0) /* System timer counter divisor */
- /* FIXME: DOSVM_GetTimer() returns quite rigid values */
- tempval = dummy_ctr+(WORD)DOSVM_GetTimer();
- else
- { /* FIXME: intelligent hardware timer emulation needed */
- tempval = dummy_ctr;
- }
- }
- switch (tmr_8253_ctrlbyte_ch[chan] & 0x30)
- {
- case 0x00:
- break; /* correct ? */
- case 0x10: /* read lo byte */
- res = (BYTE)tempval;
- break;
- case 0x30: /* read lo byte, then hi byte */
- tmr_8253_byte_toggle[chan] ^= TRUE; /* toggle */
- if (tmr_8253_byte_toggle[chan] == TRUE)
+ case 0:
+ res = 0; /* shouldn't happen? */
+ break;
+ case 1: /* read lo byte */
+ res = (BYTE)tempval;
+ tmr_8253[chan].latched = FALSE;
+ break;
+ case 3: /* read lo byte, then hi byte */
+ tmr_8253[chan].byte_toggle ^= TRUE; /* toggle */
+ if (tmr_8253[chan].byte_toggle)
{
res = (BYTE)tempval;
break;
}
/* else [fall through if read hi byte !] */
- case 0x20: /* read hi byte */
- res = (BYTE)tempval>>8;
- break;
+ case 2: /* read hi byte */
+ res = (BYTE)(tempval >> 8);
+ tmr_8253[chan].latched = FALSE;
+ break;
}
- break;
}
+ break;
case 0x60:
res = INT_Int09ReadScan(NULL);
#if 0 /* what's this port got to do with parport ? */
@@ -345,6 +348,10 @@
case 0x201:
res = 0xffffffff; /* no joystick */
break;
+ case 0x3ba:
+ case 0x3da:
+ res = (DWORD)VGA_ioport_in( port );
+ break;
default:
WARN("Direct I/O read attempted from port %x\n", port);
res = 0xffffffff;
@@ -385,10 +392,6 @@
switch (port)
{
- case 0x3c8:
- case 0x3c9:
- VGA_ioport_out( port, (BYTE)value );
- break;
case 0x20:
DOSVM_PIC_ioport_out( port, (BYTE)value );
break;
@@ -397,74 +400,79 @@
case 0x42:
{
BYTE chan = port & 3;
- WORD oldval = 0;
- if ( ((tmr_8253_ctrlbyte_ch[chan] & 0x30) != 0x30) ||
-/* we need to get the oldval before any lo/hi byte change has been made */
- (tmr_8253_byte_toggle[chan] == FALSE) )
- oldval = tmr_8253_countmax[chan];
- switch (tmr_8253_ctrlbyte_ch[chan] & 0x30)
+ /* we need to get the oldval before any lo/hi byte change has been made */
+ if (((tmr_8253[chan].ctrlbyte_ch & 0x30) != 0x30) ||
+ !tmr_8253[chan].byte_toggle)
+ tmr_8253[chan].oldval = tmr_8253[chan].countmax;
+ switch ((tmr_8253[chan].ctrlbyte_ch & 0x30) >> 4)
{
- case 0x00:
- break; /* correct ? */
- case 0x10: /* write lo byte */
- tmr_8253_countmax[chan] =
- (tmr_8253_countmax[chan] & 0xff00) | (BYTE)value;
+ case 0:
+ break; /* shouldn't happen? */
+ case 1: /* write lo byte */
+ tmr_8253[chan].countmax =
+ (tmr_8253[chan].countmax & 0xff00) | (BYTE)value;
break;
- case 0x30: /* write lo byte, then hi byte */
- tmr_8253_byte_toggle[chan] ^= TRUE; /* toggle */
- if (tmr_8253_byte_toggle[chan] == TRUE)
+ case 3: /* write lo byte, then hi byte */
+ tmr_8253[chan].byte_toggle ^= TRUE; /* toggle */
+ if (tmr_8253[chan].byte_toggle)
{
- tmr_8253_countmax[chan] =
- (tmr_8253_countmax[chan] & 0xff00) | (BYTE)value;
+ tmr_8253[chan].countmax =
+ (tmr_8253[chan].countmax & 0xff00) | (BYTE)value;
break;
}
/* else [fall through if write hi byte !] */
- case 0x20: /* write hi byte */
- tmr_8253_countmax[chan] =
- (tmr_8253_countmax[chan] & 0xff)|((BYTE)value << 8);
+ case 2: /* write hi byte */
+ tmr_8253[chan].countmax =
+ (tmr_8253[chan].countmax & 0x00ff) | ((BYTE)value << 8);
break;
}
- if (
- /* programming finished ? */
- ( ((tmr_8253_ctrlbyte_ch[chan] & 0x30) != 0x30) ||
- (tmr_8253_byte_toggle[chan] == FALSE) )
- /* update to new value ? */
- && (tmr_8253_countmax[chan] != oldval)
- )
- set_timer_maxval(chan, tmr_8253_countmax[chan]);
+ /* if programming is finished and value has changed
+ then update to new value */
+ if ((((tmr_8253[chan].ctrlbyte_ch & 0x30) != 0x30) ||
+ !tmr_8253[chan].byte_toggle) &&
+ (tmr_8253[chan].countmax != tmr_8253[chan].oldval))
+ set_timer_maxval(chan, tmr_8253[chan].countmax);
}
break;
case 0x43:
- {
- BYTE chan = ((BYTE)value & 0xc0) >> 6;
-
- /* ctrl byte for specific timer channel */
- tmr_8253_ctrlbyte_ch[chan] = (BYTE)value;
- if (chan == 3) {
- FIXME("8254 timer readback not implemented yet\n");
- }
- else
- if (((BYTE)value&0x30)==0) { /* latch timer */
- tmr_8253_latched[chan] = TRUE;
- dummy_ctr -= 1+(int) (10.0*rand()/(RAND_MAX+1.0));
- if (chan == 0) /* System timer divisor */
- tmr_8253_latch[0] = dummy_ctr+(WORD)DOSVM_GetTimer();
- else
- { /* FIXME: intelligent hardware timer emulation needed */
- tmr_8253_latch[chan] = dummy_ctr;
- }
- }
- if ((value & 0x30) == 0x30) /* write lo byte, then hi byte */
- tmr_8253_byte_toggle[((BYTE)value & 0xc0) >> 6] = FALSE; /* init */
- }
- break;
+ {
+ BYTE chan = ((BYTE)value & 0xc0) >> 6;
+ /* ctrl byte for specific timer channel */
+ if (chan == 3)
+ {
+ FIXME("8254 timer readback not implemented yet\n");
+ break;
+ }
+ switch (((BYTE)value & 0x30) >> 4)
+ {
+ case 0: /* latch timer */
+ tmr_8253[chan].latched = TRUE;
+ dummy_ctr -= 1 + (int)(10.0 * rand() / (RAND_MAX + 1.0));
+ if (chan == 0) /* System timer divisor */
+ tmr_8253[chan].latch = dummy_ctr + (WORD)DOSVM_GetTimer();
+ else
+ {
+ /* FIXME: intelligent hardware timer emulation needed */
+ tmr_8253[chan].latch = dummy_ctr;
+ }
+ break;
+ case 3: /* write lo byte, then hi byte */
+ tmr_8253[chan].byte_toggle = FALSE; /* init */
+ /* fall through */
+ case 1: /* write lo byte only */
+ case 2: /* write hi byte only */
+ tmr_8253[chan].ctrlbyte_ch = (BYTE)value;
+ break;
+ }
+ }
+ break;
case 0x61:
parport_8255[1] = (BYTE)value;
- if ((((BYTE)parport_8255[1] & 3) == 3) && (tmr_8253_countmax[2] != 1))
+ if ((((BYTE)parport_8255[1] & 3) == 3) && (tmr_8253[2].countmax != 1))
{
- TRACE("Beep (freq: %d) !\n", 1193180 / tmr_8253_countmax[2]);
- Beep(1193180 / tmr_8253_countmax[2], 20);
+ TRACE("Beep (freq: %d) !\n", 1193180 / tmr_8253[2].countmax);
+ Beep(1193180 / tmr_8253[2].countmax, 20);
}
break;
case 0x70:
@@ -473,6 +481,10 @@
case 0x71:
cmosimage[cmosaddress & 0x3f] = (BYTE)value;
break;
+ case 0x3c8:
+ case 0x3c9:
+ VGA_ioport_out( port, (BYTE)value );
+ break;
default:
WARN("Direct I/O write attempted to port %x\n", port );
break;
