diff options
| -rw-r--r-- | main.asm | 87 |
1 files changed, 86 insertions, 1 deletions
@@ -70196,7 +70196,92 @@ DeterminePaletteID: ld a, [hl] ret -INCBIN "baserom.gbc",$71FB6,$725C8-$71FB6 +INCBIN "baserom.gbc",$71FB6,$71FEB-$71FB6 + +SendSGBPacket: ;$5feb +;check number of packets + ld a,[hl] + and a,$07 + ret z +; store number of packets in B + ld b,a +.loop2\@ +; save B for later use + push bc +; load a non-zero value in $fff9 to disable the routine that checks actual +; joypad input (said routine, located at $15f, does nothing if $fff9 is not +; zero) + ld a,$01 + ld [$fff9],a +; send RESET signal (P14=LOW, P15=LOW) + xor a + ld [$ff00],a +; set P14=HIGH, P15=HIGH + ld a,$30 + ld [$ff00],a +;load length of packets (16 bytes) + ld b,$10 +.nextByte\@ +;set bit counter (8 bits per byte) + ld e,$08 +; get next byte in the packet + ld a,[hli] + ld d,a +.nextBit0\@ + bit 0,d +; if 0th bit is not zero set P14=HIGH,P15=LOW (send bit 1) + ld a,$10 + jr nz,.next0\@ +; else (if 0th bit is zero) set P14=LOW,P15=HIGH (send bit 0) + ld a,$20 +.next0\@ + ld [$ff00],a +; must set P14=HIGH,P15=HIGH between each "pulse" + ld a,$30 + ld [$ff00],a +; rotation will put next bit in 0th position (so we can always use command +; "bit 0,d" to fetch the bit that has to be sent) + rr d +; decrease bit counter so we know when we have sent all 8 bits of current byte + dec e + jr nz,.nextBit0\@ + dec b + jr nz,.nextByte\@ +; send bit 1 as a "stop bit" (end of parameter data) + ld a,$20 + ld [$ff00],a +; set P14=HIGH,P15=HIGH + ld a,$30 + ld [$ff00],a + xor a + ld [$fff9],a +; wait for about 70000 cycles + call Wait7000 +; restore (previously pushed) number of packets + pop bc + dec b +; return if there are no more packets + ret z +; else send 16 more bytes + jr .loop2\@ + +INCBIN "baserom.gbc",$7202B,$7214A-$7202B + +Wait7000: ;$614a +; each loop takes about 10 cycles so this routine actually loops through 70000 +; cycles. + ld de,$1b58 ; = 7000 +.loop\@ + nop + nop + nop + dec de + ld a,d + or e + jr nz,.loop\@ + ret + +INCBIN "baserom.gbc",$72156,$725C8-$72156 MonsterPalettes: ; 65C8 db PAL_MEWMON ; MISSINGNO |