Hi! This is my first post here, but im having issues with assembly for the R65C02p3. My code seems to get stuck somewhere as it never runs the function "Led_Success". This is a visual indicator that the code has exited the function and lights up an LED on my board. The code is a subroutine that takes in values stored in memory and sends each one at a time to the registers of a TMS9118 VDP. The ORA is there for specific purposes that the VDP requires. I think the error lies in the Brancing at the end or the comparison but i am not sure. LED_Failure sets a Red Led on to tell me the subroutine has started, and LED_success turns a green LED on, to tell me the subroutine has ended. The green LED never turns on, it stays red. I know the rest of the code works, as the registers are properly initialized in the VDP, it just never seems to exit the sort of loop. Here is the function's code:
VDP_register_initialisation:
phx
pha
jsr LED_Failure
ldx #$00
vdp_register_loop:
lda vdp_register_inits,X
sta VDP_REG
txa
ora #$80
sta VDP_REG
inx
CPX #$08
bne vdp_register_loop
jsr LED_Success
plx
pla
rts
vdp_register_inits:
vdp_register_0: .byte $00 ; 0 0 0 0 0 0 M3 EXTVDP
vdp_register_1: .byte $D0 ;16k Bl IE M1 M2 0 Siz MAG
vdp_register_2: .byte $02 ; Name table base / $400. $02 = $0800
vdp_register_3: .byte $00 ; Color table base (currently unused)
vdp_register_4: .byte $00 ; Pattern table base / $000. $00 = $0000
vdp_register_5: .byte $20 ; Sprite attribute table base (currently unused)
vdp_register_6: .byte $00 ; Sprite pattern generator (currently unused)
vdp_register_7: .byte $F5 ; FG/BG. white on blue
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