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Okay, now I understand this completely.
Thank you! =)

The use of $FF fill for EPROMs isn't really relevant for most people's workflow these days, though. I personally prefer filling with 0, because it creates a BRK opcode, which has more predictable behaviour in the accident that your program tries to execute an empty space. $FF is some weird illegal ...

tepples wrote:In ASM6, try fillvalue $FF

Ok, by default
PS "fillvalue" is useful, thanks

By the way, my little observation:
when I dealt with banks, I saw a slight difference between nasasm3 and asm6:
nesasm3 - fills the unused space 0xFF (Undefined)
while asm6 - fills 0x00 (BRK)

lda #$20 sta $2006 sta $2006 ; e.g. first page I understand it. This, just be short (sorry that without explanation, I meant writing in any position on the first page). ;index from CHR-RAM ($0-$2000) I incorrectly explained this, sorry (I understand it). ; pseudo code Yes, this is pseudocode, I und...

I seem to understand :( CHR-ROM is 0-2000$ if not CHR-ROM, then we fill it with: lda #$0 ; data ldx #$0 ; address stx $2006 stx $2006 ; pseudo code all_data: sta $2007 ; save tile/sprite bne all_data ; till $40 * $10 = first page tile/sprite bne all_data ; till $40 * $10 = second page tile/sprite (1...

sorry :
lda (src),y - is index ok, but from where (only zeropage - 0xFF size)?

I understand correctly: If the cartridge has a CHR-ROM, then CHR-RAM (0 - $2000) is filled with the data index from the CHR-ROM, but if the cartridge does not have a CHR-ROM, then the CHR-RAM is filled with data! (and not index) PRG-ROM? I better give an example ((I do not understand how to draw a t...

Hello!
I'm new to programming for nes.
It seems that everything is clear, except for one thing: if the game does not use CHR-ROM (only PRG-ROM), how does the game determine where to get the tiles/sprites (respectively for $2007/$2004)?