Charles Marslett, MYDOS and FastChip
Charles Marslett wrote floppy disk and hard drive drivers for Percom, and was the creator of MYDOS, a disk operating system for the Atari 8-bit computers that offered support for double density sectors, subdirectories, and hard drives. He also created FastChip, a hardware add-on for the Atari, sold by Newell Industries, that claimed to speed up floating point routines by 300%. He also created the A65 Assembler, a macro assembler. He has released the source code for MYDOS and FastChip.
This interview took place on July 13, 2020.
Charles' web site
MyDOS at AtariWiki
MyDOS 3.0 User Guide
A65 Assembler at AtariWiki
ANTIC Interview 212 - Wes Newell, Newell Industries
ANTIC Interview 7 - The Atari 8-bit Podcast - Bill Wilkinson, OSS
ANTIC Interview 11 - The Atari 8-bit Podcast - David Small
ANTIC Interview 22 - The Atari 8-bit Podcast - Kathleen O'Brien, OSS
Michael Abrash
Zen of Assembly Language by Michael Abrash
Zen of Assembly Language by Michael Abrash: free eBook version; code at GitHub