collapseos/emul/sms/pad.c
2020-10-24 14:37:19 -04:00

31 lines
614 B
C

#include "pad.h"
void pad_init(Pad *pad, Tristate *TH)
{
pad->pressed = 0xff;
pad->TH = TH;
}
void pad_setbtn(Pad *pad, PAD_BTN btn, bool pressed)
{
if (pressed) {
pad->pressed &= ~(1 << btn);
} else {
pad->pressed |= (1 << btn);
}
}
uint8_t pad_rd(Pad *pad)
{
uint8_t res;
if (*pad->TH == TRI_LOW) { // TH selected
// A and START shifted in from bits 7:6 into 5:4
res = (pad->pressed & 0xf) | ((pad->pressed & 0xc0) >> 2);
} else {
res = pad->pressed & 0x3f;
}
// Bits 7:6 are always high
res |= 0b11000000;
return res;
}