I stumbled across these at a garage sale, they were at the bottom of a big “$10 for the whole box” box of random electronics parts. They look to be vintage IC / EPROM chips. All various makes and models - Intel, TI, Zilog, SSS (?), Mitsubishi, AMD, NEC, SGS Thomson, Toshiba, TMS, and some others with no text names but logos that I don’t recognize. The ones that have dates are all late 70s and early 80s.
Pursuing eBay suggests that some vintage computer parts are somewhat valuable. Can anyone tell me more about vintage chips like these, and if they are worth the effort of reselling?
UV eraseable proms. Some early could chips had UV eraseable storage as well. Cool find, early to mid 80’s, maybe late 70’s for some of the Motorola and zilog stuff. Used them many times.
Sad to say, those EPROMs ain’t worth much (if anything) nowadays. I got about as many as you do in those tubes, maybe more, and will probably never use all that many more of them, ever, only because things are much more integrated today. Flash pretty much wiped out EPROM.
Even the biggest donks, like 4*meg* EPROMs, were organised like 512k×8 or 256k×16. Flash is already in the gigs, not megs, and certainly not kils.
The ones with windows where you can see the chips are UV-erasable. Cheaper variants were the exact same chips, but in plastic packages, called OTPs / one-time programmables. I’ve got 8748 microcontrollers with the windows, and some 8748-OTPs. Both of those were based on the 8048 (ROM) µC.
Those chips, back when I got them, were worth a small fortune at market prices. Now, I couldn’t give them away without also paying postage for someone to take them.
Despite being stone knives and bearskins by today’s standards, throw together a small system with a Z80, 27xxx EPROM, and 6116/6264/62256 SRAM, and you’ll feel a real sense of accomplishment!
Back in the mid 80’s when IBM PC clones were first coming out, there was a lot of software that wouldn’t work on the 8088 clones because it would make calls to the IBM basic program in the chip sets. We used these eproms and a burner to burn the IBM code and installed them on clones for those who needed them. Became unnecessary as rewritten software became available. Had a few dozen tubes of these eproms that I tossed 20 years ago. I don’t remember them being all that expensive even back then.
I eschewed the power-hungry NMOS chips (eg, 2732) and always stuck with the nice low-power CMOS chips (eg, 27C32). Plus, I always got sampled the first-out production runs of the newest’n’bestest, even critters like the ×16 chips in the 40pin packages.
Trust me, they weren’t cheap.
All my goodies could be run offa 5V wall-warts, and didn’t need 3A or 5A linear supplies.
That included all the CMOS Z80s, 80C51s, 64180s, 89C2051s, etc. Oh, and CMOS glue chips like the SC series (eg, 74SC245), and later HC series, etc. (Never liked the HCTs.)
So yeah, I always stocked up on CMOS EPROMs, too.
Hell, probably in 30-40yrs from now when flashlights are powered from dilithium nuggets and use phased-plasma to get 5000lm/W, I’ll still have boxes of XP-Es and XM-Ls in my collection…
big indian, little indian… chortle the good old days, when you actually had to be able to write in machine code… these days it seems like you pay 5 bucks, and boot up an OS, just to read a value in from a port and make a comparison, lol…
me too.
damm you Sedstar!
btw i still have a ton of the old eproms around.
i service old industrial stuff.i dump every eprom i see.so when bit rot gets em i can fix it.
common in vintage video games.i grab every rom set i can dump to add to my collection and put it out for MAME.
many a arcade game owner owes their now working game to MAME.
MAME means the code will live forever as it is stored everywhere now.this includes bootleg/unofficial stuff.
UV eraseable? was still in “common use” among the ElectricalEngineering guys at my university, that i hung around with. (electronic hobby for me, job for them)
this was around 1990 ish the guys that did microprocessor work liked them… by the time the EE guya were a senior? they were well versed enough to set up a “clock” for the bare u-processor, so as to make their own “carrier board”, and to set up the memory chips with the clocking and write/reads to the onboard memory ICs they soldered in,
i WANNA say that for EE-work at home? with u-processors? the “HC” series was kinda the de-facto standard, based on price, availability, and low parts count to make your own “proto board” and “carrier board”… those things were still too expensive for college students at the time, lol.
at the time? i was back at college for my second degree, and even though i was a computer programmer? i was older than all the “traditional students” around me, plus i had been a programmer from a young age… this made me familiar with the “old days” when you simply HAD TO know how to write machine code in z80 assembler, and tranfer your program to “byte code” so it could be used by the interpreted basic onboard all the computers in common business use at the time….
THIS made me valuable to all the EE guys, who didnt tend to be the best computer programmers, they were hardware geeks… unfortunately for them? most of the computer programming guys? well, machine code was just a class we had to take… almost no one was still programmin IN assembler anymore, let alone could make programs in byte code…
this made me the natural “go between” for all the junior and senior “EE big projects” they had to do… I got “unfettered access” to all the EE labs at all hours of the day and night… the EE guys got all their machine code written flawlessly and quickly… and my electronics hobby (wanna be HAM at the time… later on became one) went thru the roof having access to these guys and their labs/toys…
