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BigEd
PostPosted: Sun Nov 18, 2012 7:45 am 
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There's a Q&A here with Don French, the author of a symbolic assembler for the VIC-20 (a 4k RAM machine) which consumed only 1639 bytes:

http://www.mailsend-online.com/blog/?p=93 (Jim Lawless' blog)

Edit: dead link, try this - thanks to Martin_H downthread. Jim's blog is now here but hasn't got this older post.

It might be interesting to see how the code is put together.


Last edited by BigEd on Sat Dec 31, 2022 10:46 pm, edited 1 time in total.

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Arlet
PostPosted: Sun Nov 18, 2012 8:00 am 
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The symbolic assembler in the Acorn Atom was less than 1KB, but since it was integrated into the BASIC ROM, it could "cheat" by calling the rest of the ROM for things like expression evaluation, which would have taken up a lot of space otherwise.
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BigEd
PostPosted: Sun Nov 18, 2012 8:09 am 
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Good point! I suppose in this too some ROM routines other than I/O might have been used.

There are other posts on that blog which might be of interest:
http://www.google.co.uk/search?q=site:m ... :blog+6502
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BigDumbDinosaur
PostPosted: Sun Nov 18, 2012 8:24 am 
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BigEd wrote:
There's a Q&A here with Don French, the author of a symbolic assembler for the VIC-20 (a 4k RAM machine) which consumed only 1639 bytes:

http://www.mailsend-online.com/blog/?p=93 (Jim Lawless' blog)

It might be interesting to see how the code is put together.

Gee, I recall the "French Silk" assembler back in the day. It was a pretty amazing feat of coding to get the thing to fit on the VIC-20 and still have some room for a symbol table and other needed storage. Clearly a demonstration of superior programming skills on Don French's part.

The first Commodore machine I purchased was the C-64 and as soon as it came out, the MADS package. MADS was pretty fast, all things considered, being mostly constrained by the speed of the feeble 1541 floppy disk drive. The first version of it had problems with macros but that was fixed in a later revision. When I moved to a pair of SFD-1001 one MB floppy drives and IEEE-488 interface, assembly times dropped dramatically, since the disk performance was stepped up by a factor of about 5 to 1. Performance on the Lt. Kernal was even more ridiculous, especially once I learned how to hack the LK-DOS kernel to read and write files at the block level (raw throughput was around 38KB/sec on a C-64).

Ah, the good old days! :?

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DonCFrench
PostPosted: Thu Dec 29, 2022 9:39 pm 
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Arlet wrote:
The symbolic assembler in the Acorn Atom was less than 1KB, but since it was integrated into the BASIC ROM, it could "cheat" by calling the rest of the ROM for things like expression evaluation, which would have taken up a lot of space otherwise.


I believe this is inaccurate. The Acorn Atom assembler is not a symbolic assembler. It is a mnemonic assembler, which means that you can use mnemonics like BNE instead of coding the binary or hex value of the BRANCH NOT EQUAL (BNE) opcode. A symbolic assembler uses labels like ComputeTax instead of coding the actual memory address in hex or the offset to the memory address for short instructions. No assembler comes close to doing what The Assembler for the VIC does (or did, since it is no longer available). Thanks for your comment though. And sorry it took me so long to answer this. I didn't realize this forum or your comment even existed until today when I Googled for the article in which the interview with me was published.
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BigEd
PostPosted: Fri Dec 30, 2022 9:08 am 
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Welcome, Don! Good to hear from you.
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Martin_H
PostPosted: Sat Dec 31, 2022 10:06 pm 
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The link at the top is now defunct. I followed the link on the page to Jim Lawless new blog and couldn't find a copy there.

Here's a wayback machine link:
https://web.archive.org/web/20120722031 ... blog/?p=93
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BigEd
PostPosted: Sat Dec 31, 2022 10:46 pm 
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Thanks - I've added a note to the head post.
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