Slot ability modification

This is very cool. Great findings Madsiur.

I'm interested in if the slot graphics change accordingly if you change the value of the conversion data, did you try this?

2nd edit: You mean like for slot 1 if you switched 7-Flush with 3 bar swap all the 2 and 5 ? I haven't tested it.

edit: I'll look more deeply into it...probably right after the RNG assignation.

Well those graphics are loaded in a big chunk of 800 bytes and I don't how they are processed because it's a direct VRAM write from $4375 to $2118. It's not like it's different smaller graphics that are loaded and displayed individually on the reel. The game somehow make us think it's that way maybe... If we could identify when the reel stops which graph is displayed and how it would give us a better idea of which offset to change to switch them. I'm still unsure of the feasibility of this...

I had some DMA and VRAM values that helped me understanding these 2 routines. The comment might be a bit off but you can get the main process:

Code:

C1/403F:    201040      JSR $4010      (set the parameters for loading the slots menu graphics & window)
C1/4042:    A410        LDY $10           (load in Y #$380)
C1/4044:    8436        STY $36
C1/4046:    A512        LDA $12           (Load bank of the offset of the menu window graphics)
C1/4048:    A00042      LDY #$4200       (future video address of the menu)
C1/404B:    202B1A      JSR $1A2B       (display the slot menu the same way slot graphics are displayed)
C1/404E:    A20008      LDX #$0800       (graphic size in bytes of the slots graphics altogether?) <-------
C1/4053:    A200F0      LDX #$F000       (Slots graphics starting offset low and medium bytes)
C1/4056:    A00044      LDY #$4400       (future video address)
C1/4059:    A9D2        LDA #$D2       (slots graphics starting offset high byte)
C1/405B:    202B1A      JSR $1A2B      (slot graphics loader?, DMA style)<-------
C1/405E:    A20010      LDX #$1000
C1/4061:    8636        STX $36
C1/4063:    A2C07F      LDX #$7FC0
C1/4066:    A00058      LDY #$5800
C1/4069:    A9C4        LDA #$C4       (FWF position)
C1/406B:    202B1A      JSR $1A2B      (FWF font loader, DMA style)
C1/406E:    AD342F      LDA $2F34      (Wallpaper selection)
C1/4071:    2907        AND #$07
C1/4073:    8D342F      STA $2F34      (Store as wallpaper selection)
C1/4076:    0A          ASL A
C1/4077:    18          CLC
C1/4078:    6D342F      ADC $2F34      (Add in original value [now A holds wallpaper # times 3])

Here's the function that prepare the VRAM transfer or is the actual transfer, but it should reach one of the DMA routine later I think:

Code:

Graphics loading routine                Comments are for from C1/405B but the overall process is the same for other graphics

C1/1A2B:    8B          PHB             (push DB byte onto the stack so PB point to the same bank as DB?)
C1/1A2C:    48          PHA             (Push #$D2 onto the stack)
C1/1A2D:    A900        LDA #$00        (zero A ?)
C1/1A2F:    48          PHA             (push #$00 onto the stack)
C1/1A30:    AB          PLB             (DB = #$00 ?)
C1/1A31:    68          PLA             (a = #$D2)
C1/1A32:    8C1621      STY $2116        (Store #$4400 to Video address)
C1/1A35:    8E7243      STX $4372        (Store #$F000 in Source offset of the 7th DMA channel.)
C1/1A38:    8D7443      STA $4374        (Set $D2 Source bank of the 7th DMA channel.)
C1/1A3B:    A901        LDA #$01
C1/1A3D:    8D7043      STA $4370        (01 is the DMA mode)
C1/1A40:    A918        LDA #$18
C1/1A42:    8D7143      STA $4371        (Destination of the DMA transfer + $2100 ---> $2118 (Video data))
C1/1A45:    A636        LDX $36            (block of 800 bytes with slots graphics)
C1/1A47:    8E7543      STX $4375        (Size of the transfer in bytes.)
C1/1A4A:    A980        LDA #$80
C1/1A4C:    8D0B42      STA $420B        (Enables 8th DMA channel ?)         
C1/1A4F:    AB          PLB             (initial value)
C1/1A50:    60          RTS