I know it is not directly 6502 related question, but Motorola 6800 family was kind of predecessor of 6502. There is a lot of similarities in their architectures and assembly languages. For some time I've been experimenting with MC6802 - I had to just slightly modify my 6502 computer design to turn it into a platform for experimenting with Motorola processors. Unfortunately, entire fun was kind of hindered by lack of good enough assembler. I was only able to find THIS ONE. It compiles nicely under Linux, but there are some issues. Comments in single line are still being recognized as code, so compilation fails. It looks like everything after valid command in line is considered comment, which messed things up when I want to declare an array of ASCII characters for example - only first one of them is recognized. By some reason it also causes problems with Makefile scripts.

Is there some better tool, comparable to ACME or CC65?

My Java based Dev65 assembler suite supports the 6800 (and 6809). See attached.

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Andrew Jacobs
6502 & PIC Stuff - http://www.obelisk.me.uk/
Cross-Platform 6502/65C02/65816 Macro Assembler - http://www.obelisk.me.uk/dev65/
Open Source Projects - https://github.com/andrew-jacobs

I have used https://www.sbprojects.net/sbasm/index.php version 2 for 6502 and 6800 projects ... but running python under Windoze for version 3 has been an annoying crap-shoot with mixed results for me (I probably don't know what I'm doing and I'm stumbling against some configuration issues I don't quite understand).

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Got a kilobyte lying fallow in your 65xx's memory map? Sprinkle some VTL02C on it and see how it grows on you!

Mike B. (about me) (learning how to github)

I can highly recommend The Macroassembler AS. I don't use it for 6800 (yet; it is on my list of Things To Do), but I do use it actively for both 6502 and 6809 code. (It supports many other CPUs as well.) It's very featureful and the author is responsive. (I got a nice improvement to local labels the other day.)

If you need a build script for Linux, I have one here. I also help maintain a GitHub repo in which we do vendor imports on a regular basis. (Unfortunately the author doesn't make his source repo available, just source snapshots and releases.)

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Curt J. Sampson - github.com/0cjs

Currently I experiment with SBASM. It is a great tool indeed.
But I ran across strange issue. I need to calculate size of the table stored in EPROM and ten store that value in zeropage location. In ACME assembler for 6502 it is pretty straightforward task. All I need to do is:



Unfortunately it doesn't seem to work with SB ASM. It seems this asembler doesn't even like subtraction of labels in single line. So I defined additional .EQ definition:



It is calculated properly as 0x300 (size of a table). But unfortunately I wasn't able to move any further:



Causes:



And this code:



Ends up with:

sbasm doesn't use < and > that way:

from https://www.sbprojects.net/sbasm/expressions.php ...

So you should try it this way and let us know if it works:

In 6800 land, it's nice to be able to save a few bytes and a few cycles if your 16-bit X register is available:

_________________
Got a kilobyte lying fallow in your 65xx's memory map? Sprinkle some VTL02C on it and see how it grows on you!

Mike B. (about me) (learning how to github)