EPROM UV erase and programming with Arduino - Page 1
Forum section: electronics / projects

author: MrWifiHifi
author_rank: Regular Contributor
timestamp: June 12, 2019, 08:50:43 am
content: HelloI have bunch of EPROM memory chips and I want to use themBut I never erase a single EPROM chipCan someone help me and give some advice how to erase and what I can use to erase EPROM chips...?I want to use Arduino to program EPROM, I've seen some designs but is it possible to make universal programmer, so I can program 2716, 2732, 2764, 27128, 27256 and 27515 chips

author: HB9EVI
author_rank: Frequent Contributor
timestamp: June 12, 2019, 08:58:27 am
content: with a bigger Atmega is certainly possible building a programmer, but if it's worth it to write all the code I don't know. I bought me a TL866 programmer which is doing very well for those parallel eproms.But actually I never bother working with UV erasable chips since there are enough EEPROMs on the market; I stuck for my Z80 project with the AT28C256

author: amyk
author_rank: Super Contributor
timestamp: June 12, 2019, 11:18:19 am
content: Search online stores for "EPROM eraser" and you'll find plenty.As for programming, you need a carefully regulated supply voltage and timed pulses --- see the datasheets for details.But this feels more like a case of "if you have to ask..."; you need to do a lot more research yourself first.

author: NivagSwerdna
author_rank: Super Contributor
timestamp: June 12, 2019, 11:28:25 am
content: Quote from: MrWifiHifi on June 12, 2019, 08:50:43 amAnything is possibleYou really need to look at the datasheet for the chips you have as different manufacturers have different programming algorithms. You are going to need some high voltage... >=21V for some chips and some reasonably accurate timings but very do-able, especially with a 5V device. It's normally a case of just sending data and address whilst proving some oompf to VPP, perhaps raising VDD at the same time.If it's not your sort of fun... just buy a commercial programmer.

author: David Hess
author_rank: Super Contributor
timestamp: June 12, 2019, 06:42:32 pm
content: Erasing may be possible using an ultraviolet LED. I think the requirement is 400 nanometers or shorter so maybe a part like this:https://www.mouser.com/ProductDetail/VCC/VAOL-5EUV8T4?qs=sGAEpiMZZMuCm2JlHBGefiok2zGXgOgqXT6BUoctcRU%3DReal UVEPROM erasers used a UVC germicidal bulb like this:https://www.amazon.com/s?k=germicidal+bulb&ref=nb_sb_nossAs other pointed out, a regulated and controlled high voltage source of about 24 volts is required. The exact voltage depends on the specific UVEPROM. Other than that and the timing requirements, programming is relatively straightforward although not all manufacturers openly documented this.

author: coromonadalix
author_rank: Super Contributor
timestamp: June 13, 2019, 02:34:49 am
content: And as other have pointed out, why complicate things .. wiring problems, sockets, timing issues, just buy an original tl866cs (jtag port) not the tl866 plus or called (II)and the infrared led can workYou have tons of small cheap eeproms programmers on the market ...Google is your friend:https://github.com/beneater/eeprom-programmerhttps://forum.arduino.cc/index.php?topic=163682.0https://github.com/TomNisbet/TommyPROM

author: rcbuck
author_rank: Frequent Contributor
timestamp: June 14, 2019, 02:50:01 am
content: OP mentioned UV erase in the title. But the part numbers do not indicate UV parts. To erase an EPROM chip it must have a glass window. And those parts are all ceramic packages. Standard DIP packages cannot be erased with a UV source.Back before flash became common you had to use the UV parts for program development or you would waste a lot of OTP parts. I have several different versions of UV PIC chips and a handful of UV EPROMS.The light frequency that is used to erase those parts is dangerous to the human eye. My eraser is in an enclosure that will not turn on until the lid is closed.

author: David Hess
author_rank: Super Contributor
timestamp: June 14, 2019, 04:19:08 pm
content: Quote from: rcbuck on June 14, 2019, 02:50:01 amQuartz is used for the erase window. Common glasses block UVC and UVC lamps also use quartz envelopes.X-rays also work to erase floating gate memory so a plastic OTP part can be erased by an x-ray generator but this is not very practical.