Re: [Freedos-user] DOS ASM resources

[Bret J. <bre...@ju...>]

> Interestingly enough, I also bought a86/D86, and have found it to be
> the best assembler/disassembler I've ever found for dos.  I ran
> across it after (mostly) trying to use debug for things, so it was a
> welcome relief.

I still like A86/A386 also, but like I said my programs are getting so complicated these days that they no longer work because of the limited memory.  Specifically, I have so many symbols (structure elements and equates and labels) that the symbol table overflows when using A86/A386.  That's why I've had to switch to something more capable (specifically, NASM).  The problem I have with NASM, and most other assemblers, is that they don't come with a useful debugger.

To me, the real "gems" of A86/A386 are the D86/D386 debuggers.  I still use them all the time when I'm debugging the programs I'm writing.  There are two things I really like about D86/D386.  One is that you can put the screen in a 50-line mode and have the debugger "window" on the top half of the screen and watch the program output on the bottom half of the screen.  That's a very nice setup.

The other thing is that if you create a .SYM (Symbol) file in the D86/D386 format you can refer to the symbol names instead of memory addresses as you are debugging, another VERY useful feature.  Unfortunately, the .SYM file format is proprietary and can only be generated by an A86 or A386 assembler.  But I have a method automated where I can take the .MAP output file generated by NASM and create the .SYM file (I only convert the subroutine labels and not the equates or structure elements) so I can use the symbolic capabilities of the D386 debugger with NASM-generated programs.  This makes debugging much easier.

I've also experimented a little bit with 386SWAT, but haven't used it enough to really get comfortable with it.  I know you can also provide symbols to 386SWAT which definitely helps.  But my main debugger is D386.

I also sometimes use ECM's lDebug, but that is mostly when I'm trying to figure out what someones else's program is doing and don't have the source code or some other way to look at the symbols/names to help try and figure out what's going on.  lDebug is much better/easier than D86/D386 for certain kinds of debugging/research.