static void stream_request_cb(pa_stream *s, size_t length, void *data) {
M6502 *mpu = (M6502 *) data;
int max = 0;
redraw = 0;
pa_stream_begin_write(s, (void**) &sndbuf, &length);
memset(sndbuf, 128, length);
max = length * 6250 / 539;
if (max > 20454)
fprintf(stderr, "Cycles = %u!\n", (unsigned int) max);
cycles = 0;
while (cycles < max) {
if (trace)
M6502_disassemble(mpu);
cycles += M6502_run(mpu);
}
pa_stream_write(s, sndbuf, length, NULL, 0, PA_SEEK_RELATIVE);
redraw = 1;
}
int main()
{
M6502 *mpu = M6502_new(0, 0, 0); /* Make a 6502 */
unsigned pc = 0x1000; /* PC for 'assembly' */
/* Install the two callback functions defined above.
*/
M6502_setCallback(mpu, call, WRCH, wrch); /* Calling FFEE -> wrch() */
M6502_setCallback(mpu, call, 0, done); /* Calling 0 -> done() */
/* A few macros that dump bytes into the 6502's memory.
*/
# define gen1(X) (mpu->memory[pc++]= (uint8_t)(X))
# define gen2(X,Y) gen1(X); gen1(Y)
# define gen3(X,Y,Z) gen1(X); gen2(Y,Z)
/* Hand-assemble the program.
*/
gen2(0xA2, 'A' ); // LDX #'A'
gen1(0x8A ); // TXA
gen3(0x20,0xEE,0xFF); // JSR FFEE
gen1(0xE8 ); // INX
gen2(0xE0, 'Z'+1 ); // CPX #'Z'+1
gen2(0xD0, -9 ); // BNE 0x1002
gen2(0xA9, '\n' ); // LDA #'\n'
gen3(0x20,0xEE,0xFF); // JSR FFEE
gen2(0x00,0x00 ); // BRK
/* Just for fun: disssemble the program.
*/
{
char insn[64];
uint16_t ip= 0x1000;
while (ip < pc)
{
ip += M6502_disassemble(mpu, ip, insn);
printf("%04X %s\n", ip, insn);
}
}
/* Point the RESET vector at the first instruction in the assembled
* program.
*/
M6502_setVector(mpu, RST, 0x1000);
/* Reset the 6502 and run the program.
*/
M6502_reset(mpu);
M6502_run(mpu);
M6502_delete(mpu); /* We never reach here, but what the hey. */
return 0;
}