Questions tagged [eprom]
Erasable Programmable Read-Only Memory, which is a type of non-volatile memory that can be programmed by an electronic device and erased by exposure to ultraviolet light.
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EPROMs /OE switching Circuit
For a personal project I'm trying to make a reproduction of a SNES game (Earthbound) which is 3mb in size.
Now the easiest way would be fitting the game in a 4mb 27C322 and multiplex the 16 bit bus to ...
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how to determine what chip wire allows BIOS flashing?
how to determine what chip wire/leg allows BIOS flashing?
I want to modify my MOBO to deny BIOS flashing.
I only want it allowed when I really need to write on it.
So, I need to know:
if it is ...
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Needing some EPROM breadboard help!
I'm currently trying to make an EPROM programmer on my breadboard capable of programming a single address at a time. Nothing fancy for writing large programs, just trying to learn some basics.
Right ...
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Recognizing an erasable EPROM from a non-erasable one
I'm a Software Engineer looking at some datasheets for electronic components, and I've come across an inconsistency that I can't make sense of.
I'm looking at PROMs, specifically EPROMs, my thought ...
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Looking for information spec sheet on an old PROM chip (GI 9128B-1180)
I just stumbled on an Apple II "clone" that uses a GI 9128B-1180 chip for the ROM.
The curious thing about it is the wire soldered on a leg. So, my hypothesis is that they didn't have the ...
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EPROM data retention lifetime? Older instruments possibly due to fail?
I have EXPENSIVE old HP instruments that are from the 1980's that work great and are certainly very good instruments, completely usable in the home lab. Each has between 4 and 12 of the old UV type ...
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Customising audio on an arcade game with U6295 audio IC
I have an arcade redemption game that has a U6295 audio IC that plays 4 different soundtracks which are stored on a ST M27C801 EPROM.
I would like to flash my own audio onto that EPROM with one of ...
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FE Exam Question
Can anyone answer the question below? I have links to pictures of the question and answer. I don't understand the answer provided by the book. Why does it say in the answer, "The EPROM will ...
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Why am I seeing -5 V or lower on the output pins reading an Intel 1702A EPROM?
I am building a breadboard/Arduino reader to dump the data on a very old Intel 1702A EPROM chip. (data sheet) When doing some basic testing by tying all the address pins to ground, I am seeing ...
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How to generate +5 V and -9 V voltages to read an Intel 1702A EPROM via Arduino?
I have some simple experience with TTL logic and Arduino, but I'm only a hobbyist and am bit stymied by my current project, which is attempting to read the data from an old Intel 1702A EPROM. The ...
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Problem with IC chips, Eprom and LCD Screen
EDIT: I have made the changes suggested with the &gate and the 555 timer to get the (E) enable pulse. I hooked up a debounced switch so I could walk through step by step. This highlighted some ...
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Erasing and Reprogramming old EPROMS
One of my customers brought in several old EPROMs that he wishes to be re-programmed with the current firmware their system is using.
My usual way of dealing with this is to place the EPROMs in the ...
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Problem with understanding EPROMs and how they're written to
I've got a problem understanding how an EPROM (UV-erasable) works.
This question may seem very dumb, but what would happen, if I just try to write contents to an EPROM, which has already been written ...
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Does providing a noisy Vpp for a short period of time affect programming an EPROM?
I have been designing a complex(from my perspective) EPROM Programmer with an ARM-based STM32f103C MCU -actually it's a bluepill board- , I already programmed my EPROM before by hand manually and even ...
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Can cells get burned in EPROM by programming twice?
I have ordered my monthly electronic components dosage online, due to the covid-19 disease... in my dosage and for the first time I got an UV EPROM and started a personal challenge of programming it ...
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Trying to program EPROMs with GQ-4X - 9/10 are failing with a few random bits wrong
I have a bunch of old/cheap EPROMs which i am trying to program.
To do this, I am using an GQ-4X.
Starting with blank EPROMs (using a UV eraser thew blank checking them), my hit rate seems to be able ...
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Combining two schematics of 1kx3 NOR MOS PROM components into a 2kx6 PROM component
Today after class we were left with an exercise of creating schematics and combining two components we learned about today. The exercise is to combine two 1kx3 NOR MOS PROM components into a 2kx6 PROM ...
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old 80C31 circuit not working. EPROM data retention issue?
I have an old piece of pro-audio gear in for repair. It dates from 1990. It was a fairly high-end piece of gear at the time and still has some value so it is worth repairing. But the symptoms I see ...
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Can an EPROM be "refreshed" without UV erasing?
I have lots of AM27C512 EPROMS (with the UV window) which are quite old (1980's.) Using a Xeltek SuperPro 3000U, most can still be read and verified. A few have failed outright and were replaced.
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EPROM memory - the theoretical possibility of recovering data from memory after erasing the exposure with ultraviolet light?
I have a small question.
We have a EPROM memory.
Is there a theoretical possibility of recovering data from memory after deleting with ultraviolet light?
Is this theoretically possible?
Or maybe it ...
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Switch between power and signal with MCU
I am trying to make a basic EPROM programmer using an Arduino. It is designed to programme M27c322/160/800 devices.
One problem I am encountering is that these 3 devices have a couple of the pins ...
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EPROM programmer voltage/signal switch
I am trying to make a basic EPROM programmer for M27C322/160/800 chips, mainly as an learning exercise since I know I can buy adaptors for programmers I already own.
I found a very useful resource in ...
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Is it safe to reconnect a presumably broken PROM connector pin?
I am trying to understand (and fix) a soda machine that doesn't seem to accept 1€ and 2€ coins while all stickers (inside and outside) seem to imply that they should work (5ct to 50ct do work).
I ...
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How to replace TTL PROMs in a design operating at 20MHz
I am attempting to come up with a reasonable way of implementing a design that was intended for cheap computer applications in the 1980s and which was originally designed to use a pair of TTL PROMs (a ...
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