On Tue, Sep 5, 2023 at 11:42 AM Herbert Johnson via vcf-midatlantic <vcf-midatlantic@lists.vcfed.org> wrote:
ow common and costly were EEPROM burners in the early 1980s?
I couldn't afford one then, but someone in our PET User Group had one (more on that below)
I’m watching Adrain’s Digital Basement where he covers the Apple II clones. Was it pretty cheap to buy large enough blank EEPROMs and then copy them yourself... < I suggest you look back further, to the mid-1970's. There were computers and EPROMs back then too...
ISTR I have a mid-70s Popular Electronics issue with a 1701 burner project.
A number of small companies, offered their own EPROM burners, that ran as serial devices usually connected to the computers (or terminals) of the era. There were also Apple II cards, and S-100 cards, and SS-50 cards - as EPROM burners.
I have a Z-80 "Starter Kit" with a built-in EPROM burner. There are a couple of switches to throw to enable programming, but the SBC has a burner built right into the kit.
Why would hobby computer owners, burn EPROMs in the early 80's? To put software into early computers, especially before floppy-disk systems became affordable and available
Starting in the late 70s, when PETs had 3 (later 2) open firmware sockets, it was common for PET owners to buy or burn firmware utilities. There were several BASIC extension ROMs, upgraded machine language monitors, and I even had a ROM-based tape accelerator (PET Rabbit). I got my start with machine language with the built-in descendant of TIM, but when I got MicroMON from one of the guys at the PET User Group, it included a line-at-a-time non-symbolic assembler/disassembler which _really_ accelerated my learning 6502 code. ISTR the bare 2532s were well over $10 each then (1979-1982) but they plugged right into a 2332 mask-programmed ROM socket. I have, in recent years, shared my firmware loadout on Zimmers. I had two 4K programs and two 2K programs filling up my 12K. For people that had more firmware extensions or who needed to swap out programs at the same address range, there were several ROM socket switchers, but I never got one. The PET didn't have a cartridge port, so this is how we expanded it (the VIC-20 and the C-64 were easier to expand this way). The advantages of this were two-fold - I was on cassettes only (no floppy drive) so I didn't have to load the utilities - they were always there. Also, they didn't cut into my 32K of RAM which was a nice bonus. Just one angle on burned ROMs and 70s/80s machines. As Herb said, the S-100 arena had its own corner for things (usually peripheral kits or customized boot ROMs since most S-100s had floppy drives and wanted the maximum amount of open RAM to load programs into) -ethan