Thank you all very much.
Yes, there are two ROMS that will work in the same system at the same time. The existing ROM has the addresses $E000 - $FFFF and the other ROM has the new addresses $A000-$BFFF .
I get the impression it will be easiest if I write the code in one, with the corresponding ...

Hello dear forum members

I am currently building an Apple 1 -like computer and now want to add a second ROM. Therefore, I'd like to split my already existing code into two parts for two ROMs and add more code later.

How can I use assembler labels meant for one ROM in the code of the other ROM ...

Thanks for all your ideas and comments. The version of my Kowalski program is 1.2.11 - I saw somewhere that there is a newer version, but I don't think that's the problem. Using Wine with Kowalski is more the difficulty. I've already experimented with ca65, I don't have the documentation for some ...

I have always written my programs for various SBC 6502 projects with Kowalski 6502 and then run the assembler and burn the ROMs.
Unfortunately Kowalski works worse and worse with wine, on my new Linux system it just hangs and crashes.
Which assembler would you recommend - possibly for Linux - if I ...

Thank you very much indeed !

All you guys helped me a lot, and after quickly changing all local labels to global ones, as BDD explained - it worked !! Well, now I can go on with the real task, which is debugging. That's great.

What I am doing is obviously a hobby. It's wonderful to know you in ...

The difference between my file version 3 (_ver3) and version4 (_ver4) is only row 415 and 416. Please have a look at it.

The assembler tells that .printacc is an unknown label name, though it has been used havily before. _ver3 works (using .printacc many times)

I don't understand what I'm doing ...

Hello everybody,

First of all, I have to tell you that I'm relatively new to assembler.
For my homebrew 6502 project I took "Kowalski"s 6502 assembler and simulator to program the ROM because it looked very simple to use.
I also took some code-parts I found in the internet (e.g. Daryl Rictors PC ...

Hello,

well, after a bit of reading I now will probably use a V9958/38 or similar (was compatible to TMS 9918). The VIC seems to compliocated to use and the extra Video RAM seems to be so much better that it is worth buying a new chip.

Now I would like to have some helpful hints (would be great ...

Hello friends,

thank you very much for all your precious help and advice !!

I've found a 6561. To be honest I'm not sure if I should be happy or not. I must have pulled it out from a VIC20 maybe 25 years ago but didn't remember that. I have read the datasheet - argh... Anyway it will take me a ...

Hello everybody !! I'm new to this forum !!

I'm currently building a rather simple 6502 based-homebrew computer. I luckyly found some very interesting information on the internet and this site. I'm very thankfull for all these informations !

So far I had a 6502, ROM, RAM, 6522, a small 16-keys ...