Function valid_programmed_mode

src/custom.cpp:1845–1864

do not switch to H/V sync cable mode if required programmed mode registers are uninitialized

// do not switch to H/V sync cable mode if required programmed mode registers are uninitialized
static bool valid_programmed_mode(void)
{
	if (beamcon0 & (BEAMCON0_VARHSYEN | BEAMCON0_VARCSYEN)) {
		if (!programmed_register_accessed_h) {
			return false;
		}
		if (hsstrt == 0xffff || hsstop == 0xffff) {
			return false;
		}
	}
	if (beamcon0 & (BEAMCON0_VARVSYEN | BEAMCON0_VARCSYEN)) {
		if (!programmed_register_accessed_v) {
			return false;
		}
		if (vsstrt == 0xffff || vsstop == 0xffff) {
			return false;
		}
	}
	return true;
}

/* set PAL/NTSC or custom timing variables */
static void init_beamcon0(void)