void play_sfx(const pcspkt_ent_list *pl) {
struct pcspk_ent *p;
t8254_time_t pc,cc;
t8254_time_t delta;
int32_t tim = 0;
p = *(pl++);
cc = read_8254(0);
while (p != NULL) {
while (p->delay != 0) {
if (p->freq != 0) {
#ifdef TARGET_PC98 /* Double the counter to convert IBM PC timer delay (1193182Hz) to PC-98 timer delay (2457600Hz) */
write_8254_pc_speaker(p->freq << 9u);
#else
write_8254_pc_speaker(p->freq << 8u);
#endif
t8254_pc_speaker_set_gate(PC_SPEAKER_GATE_ON);
}
else {
t8254_pc_speaker_set_gate(PC_SPEAKER_GATE_OFF);
}
#ifdef TARGET_PC98 /* Double the delay to convert IBM PC timer delay (1193182Hz) to PC-98 timer delay (2457600Hz) */
tim += (int32_t)((unsigned long)p->delay << 9u);
#else
tim += (int32_t)((unsigned int)p->delay << 8u);
#endif
while (tim >= 0l) {
pc = cc;
cc = read_8254(0);
delta = (pc - cc) & 0xFFFFul; /* counts DOWN */
tim -= delta;
}
p++;
}
p = *(pl++);
}
t8254_pc_speaker_set_gate(PC_SPEAKER_GATE_OFF);
}
void pulse_width_test() {
int fd;
unsigned char cc;
unsigned int play;
unsigned char plan_b=0;
unsigned int patience = 10000;
_cli();
write_8254_system_timer(0xFFFF); /* BUGFIX: Personal experience tells me BIOSes would fail reading the floppy if the IRQ 0 timer isn't ticking along at 18Hz */
_sti();
fd = open("..\\test1_22.wav",O_RDONLY|O_BINARY);
if (fd < 0) fd = open("test1_22.wav",O_RDONLY|O_BINARY);
if (fd < 0) {
fprintf(stderr,"Cannot open test WAV\n");
return;
}
lseek(fd,44,SEEK_SET);
read(fd,tmp,sizeof(tmp));
for (play=0;play < sizeof(tmp);play++) tmp[play] = (((tmp[play]) * 53) / 255) + 1; /* add "noise" to dither */
close(fd);
/* set timer 0 to 54 ticks (1.191MHz / 54 ~ 22050Hz) */
_cli();
t8254_pc_speaker_set_gate(0);
write_8254_pc_speaker(1);
write_8254_system_timer(54);
_sti();
_cli();
{
outp(T8254_CONTROL_PORT,(0 << 6) | (0 << 4) | 0); /* latch counter N, counter latch read */
do {
if (--patience == 1) break;
cc = inp(T8254_TIMER_PORT(0));
inp(T8254_TIMER_PORT(0));
} while (cc < (54/2));
do {
if (--patience == 0) break;
cc = inp(T8254_TIMER_PORT(0));
inp(T8254_TIMER_PORT(0));
} while (cc >= (54/2));
if (patience <= 2) {
write_8254_system_timer(0xFFFF); /* BUGFIX: on very old slow machines, the 54-count tick can easily cause the printf() below to absolutely CRAWL... */
_sti();
fprintf(stderr,"Oops! Either your CPU is too fast or the timer countdown trick doesn't work.\n");
_cli();
write_8254_system_timer(54);
plan_b = 1;
}
}
_sti();
while (1) {
if (kbhit()) {
int c = getch();
if (c == 27) break;
}
if (plan_b) {
/* run with interrupts enabled, use IRQ0 to know when to tick */
_cli();
counter = 0;
t8254_pc_speaker_set_gate(3);
for (play=0;play < sizeof(tmp);) {
outp(T8254_CONTROL_PORT,(2 << 6) | (1 << 4) | (T8254_MODE_0_INT_ON_TERMINAL_COUNT << 1)); /* MODE 0, low byte only, counter 2 */
outp(T8254_TIMER_PORT(2),tmp[play]);
_sti();
while (counter == 0);
_cli();
play += counter;
counter = 0;
}
_sti();
}
else {
_cli();
t8254_pc_speaker_set_gate(3);
outp(T8254_CONTROL_PORT,(0 << 6) | (0 << 4) | 0); /* latch counter N, counter latch read */
for (play=0;play < sizeof(tmp);play++) {
outp(T8254_CONTROL_PORT,(2 << 6) | (1 << 4) | (T8254_MODE_0_INT_ON_TERMINAL_COUNT << 1)); /* MODE 0, low byte only, counter 2 */
outp(T8254_TIMER_PORT(2),tmp[play]);
do {
cc = inp(T8254_TIMER_PORT(0));
inp(T8254_TIMER_PORT(0));
} while (cc < (54/2));
do {
cc = inp(T8254_TIMER_PORT(0));
inp(T8254_TIMER_PORT(0));
} while (cc >= (54/2));
}
_sti();
}
}
t8254_pc_speaker_set_gate(0);
}
int main() {
struct t8254_readback_t readback;
t8254_time_t tick[3];
unsigned int i;
printf("8254 library test program\n");
if (!probe_8254()) {
printf("Chip not present. Your computer might be 2010-era hardware that dropped support for it.\n");
return 1;
}
if (!probe_8259()) {
printf("8259 interrupt controller not present. Your computer might be 2010-era hardware that dropped support for it.\n");
return 1;
}
printf("8254 base clock: %luHz\n",T8254_REF_CLOCK_HZ);
speaker_rate = T8254_REF_CLOCK_HZ / 400UL; /* 400Hz */
prev_irq0 = _dos_getvect(T8254_IRQ+0x08);
_dos_setvect(T8254_IRQ+0x8,irq0);
_cli();
write_8254_pc_speaker(speaker_rate);
write_8254_system_timer(max);
_sti();
#ifdef TARGET_PC98
/* PC-98 does not have IRQ0 running by default */
p8259_unmask(T8254_IRQ);
#endif
while (1) {
if (kbhit()) {
int c = getch();
if (c == 27)
break;
else if (c == '-') {
max -= 80;
if (max > (0xFFFF-80))
max = 0xFFFF;
_cli();
write_8254_system_timer(max);
_sti();
}
else if (c == '=') {
max += 110;
if (max < 110 || max > (0xFFFF-110))
max = 0xFFFF;
_cli();
write_8254_system_timer(max);
_sti();
}
/* play with timer 2 and the PC speaker gate */
else if (c == 'p') {
unsigned char on = (t8254_pc_speaker_read_gate() != 0) ? 1 : 0;
if (on) t8254_pc_speaker_set_gate(0);
else t8254_pc_speaker_set_gate(3);
}
else if (c == '1') {
#ifndef TARGET_PC98
unsigned char v = t8254_pc_speaker_read_gate();
t8254_pc_speaker_set_gate(v ^ PC_SPEAKER_OUTPUT_TTL_AND_GATE);
#endif
}
else if (c == '2') {
#ifndef TARGET_PC98
unsigned char v = t8254_pc_speaker_read_gate();
t8254_pc_speaker_set_gate(v ^ PC_SPEAKER_COUNTER_2_GATE);
#endif
}
else if (c == '[') {
speaker_rate += 110;
if (speaker_rate > (0xFFFF-110) || speaker_rate < 110)
speaker_rate = 0xFFFF;
write_8254_pc_speaker(speaker_rate);
}
else if (c == ']') {
speaker_rate -= 110;
if (speaker_rate > (0xFFFF-110))
speaker_rate = 0;
write_8254_pc_speaker(speaker_rate);
}
else if (c == 'w') {
printf("\n");
pulse_width_test();
_cli();
write_8254_system_timer(max);
_sti();
printf("\n");
}
else if (c == 'z') {
/* sleep-wait loop test */
unsigned long delay_ticks;
unsigned long z;
unsigned int c,cmax;
printf("\nDelay interval in us? ");
z = 1000000; scanf("%lu",&z);
delay_ticks = t8254_us2ticks(z);
printf(" %lu = %lu ticks\n",z,delay_ticks);
if (delay_ticks == 0UL) cmax = (unsigned int)(T8254_REF_CLOCK_HZ / 20UL);
else cmax = (unsigned int)(T8254_REF_CLOCK_HZ / 20UL / (unsigned long)delay_ticks);
if (cmax == 0) cmax = 1;
write_8254_pc_speaker(T8254_REF_CLOCK_HZ / 400UL); /* tick as fast as possible */
while (1) {
if (kbhit()) {
if (getch() == 27) break;
}
for (c=0;c < cmax;c++) {
t8254_pc_speaker_set_gate(3);
t8254_wait(delay_ticks);
t8254_pc_speaker_set_gate(0);
t8254_wait(delay_ticks);
}
}
}
else if (c == 'd') {
printf("\n \nDetail mode, hit 'd' again to exit: [WARNING: 8254 only]\n");
while (1) {
if (kbhit()) {
int c = getch();
if (c == 'd') {
break;
}
}
_cli();
readback_8254(T8254_READBACK_ALL,&readback);
_sti();
printf("\x0D");
for (i=0;i <= 2;i++) {
printf("[%u] stat=%02x count=%04x ",i,
readback.timer[i].status,
readback.timer[i].count);
}
fflush(stdout);
}
printf("\n");
}
}
for (i=0;i <= 2;i++) tick[i] = read_8254(i);
/* BUG: DOSBox/DOSBox-X appear to have a bug where the PC speaker readback toggles
* regardless of the GATE input to Counter 2. Bring GATE low (setting bit 1
* of port 61h to 0) is supposed to cause Counter 2 to stop. The AND gate
* after the output (bit 0 of port 61h) is not supposed to affect the readback. */
printf("\x0D %04x %04x %04x max=%04x count=%04x SPKR=%u",tick[0],tick[1],tick[2],
max,counter,read_8254_pc_speaker_output()!=0?1:0);
fflush(stdout);
}
printf("\n");
#ifdef TARGET_PC98
/* PC-98 does not have IRQ0 running by default */
p8259_mask(T8254_IRQ);
#endif
_cli();
write_8254_pc_speaker(0);
t8254_pc_speaker_set_gate(0);
_dos_setvect(T8254_IRQ+0x8,prev_irq0);
_sti();
write_8254_system_timer(0xFFFF); /* restore normal function to prevent BIOS from going crazy */
return 0;
}
