Some time ago I tried to do a game similar to Bomber Man. The main reason was the curiosity I could do with my low programming capabilities ... I had some problems, but I could almost copy the basics of this game. Of course, still a long way to go and I have some things I can not solve.

The first thing to do is to calculate / extract ATTRIBUTE TABLE so that it accurately matches the location of the bomb. The bomberman bomb has a different palette than its explosion (changing the palette in the attribute table). In my demo of the game, the place of the bomb is also copied to RAM variables BombY_Temp and BombX_Temp. Maybe their position would be good to calculate the position of this place on the screen in the Attribute Table? The problem is that one byte (two bits per single 16x16 field) in this array corresponds to four 16x16 pix fields on the screen, I do not know how to calculate it.

I would like some tips on how to make randomly moving opponents. The one I did in this demo came out pretty weak.

Another thing is the best way of animating a background in UNROM (it is not possible to animate the background using CHR bank switching). Originally the code I have under UNROM, but the demo I have now moved to the CNROM where animating the bomb is by switching CHR banks. However, I would prefer UNROM.

Link to an earlier topic where I asked for help with the bomb code.

https://forums.nesdev.com/viewtopic.php?f=10&t=16256Sample code I used to animate the bomb and its explosion in UNROM:

Unfortunately it overloads the NMI (VBLANK), which crashes in NTSC (in the PAL barely). I have no idea how to do this as efficiently as possible.

**Code:**

Bomb_Anim_no:

RTS

Bomb_Anim: ;in NMI loop

INC Bomb_Anim_Timer ;timer

INC Bomb_Anim_Timer

INC Bomb_Anim_Timer

INC Bomb_Anim_Timer

LDA Bomb_Anim_Timer

CMP #$00

BCC BA_no1

LDA BOMB_PPU_TILE1_AddrHI

STA $2006

LDA BOMB_PPU_TILE1_AddrLO

STA $2006

lda #$10 ;pattern table bgr tile1 nr.

sta $2007

LDA BOMB_PPU_TILE1_AddrHI

STA $2006

LDA BOMB_PPU_TILE2_AddrLO

STA $2006

lda #$11 ;pattern table bgr tile2 nr.

sta $2007

LDA BOMB_PPU_TILE1_AddrHI

STA $2006

LDA BOMB_PPU_TILE3_AddrLO

STA $2006

lda #$20 ;pattern table bgr tile3 nr.

sta $2007

LDA BOMB_PPU_TILE1_AddrHI

STA $2006

LDA BOMB_PPU_TILE4_AddrLO

STA $2006

lda #$21 ;pattern table bgr tile4 nr.

sta $2007

; LDA #$00 ;reset screen (Not needed, there is one at the end of the NMI loop.)

; STA $2006

; LDA #$00

; STA $2006

BA_no1:

LDA Bomb_Anim_Timer

CMP #$40

BCC BA_no2

LDA BOMB_PPU_TILE1_AddrHI

STA $2006

LDA BOMB_PPU_TILE1_AddrLO

STA $2006

lda #$12

sta $2007

LDA BOMB_PPU_TILE1_AddrHI

STA $2006

LDA BOMB_PPU_TILE2_AddrLO

STA $2006

lda #$13

sta $2007

LDA BOMB_PPU_TILE1_AddrHI

STA $2006

LDA BOMB_PPU_TILE3_AddrLO

STA $2006

lda #$22

sta $2007

LDA BOMB_PPU_TILE1_AddrHI

STA $2006

LDA BOMB_PPU_TILE4_AddrLO

STA $2006

lda #$23

sta $2007

; LDA #$00

; STA $2006

; LDA #$00

; STA $2006

BA_no2:

LDA Bomb_Anim_Timer

CMP #$80

BCC BA_no3

LDA BOMB_PPU_TILE1_AddrHI

STA $2006

LDA BOMB_PPU_TILE1_AddrLO

STA $2006

lda #$14

sta $2007

LDA BOMB_PPU_TILE1_AddrHI

STA $2006

LDA BOMB_PPU_TILE2_AddrLO

STA $2006

lda #$15

sta $2007

LDA BOMB_PPU_TILE1_AddrHI

STA $2006

LDA BOMB_PPU_TILE3_AddrLO

STA $2006

lda #$24

sta $2007

LDA BOMB_PPU_TILE1_AddrHI

STA $2006

LDA BOMB_PPU_TILE4_AddrLO

STA $2006

lda #$25

sta $2007

; LDA #$00

; STA $2006

; LDA #$00

; STA $2006

BA_no3:

LDA Bomb_Anim_Timer

CMP #$C0

BCC BA_no4

LDA BOMB_PPU_TILE1_AddrHI

STA $2006

LDA BOMB_PPU_TILE1_AddrLO

STA $2006

lda #$12

sta $2007

LDA BOMB_PPU_TILE1_AddrHI

STA $2006

LDA BOMB_PPU_TILE2_AddrLO

STA $2006

lda #$13

sta $2007

LDA BOMB_PPU_TILE1_AddrHI

STA $2006

LDA BOMB_PPU_TILE3_AddrLO

STA $2006

lda #$22

sta $2007

LDA BOMB_PPU_TILE1_AddrHI

STA $2006

LDA BOMB_PPU_TILE4_AddrLO

STA $2006

lda #$23

sta $2007

; LDA #$00

; STA $2006

; LDA #$00

; STA $2006

BA_no4:

RTS