EPROM programmer software?

super56k

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I would like to get more into reading/programming EPROMS but I don't know what software to use.

I recently picked up one of these:
http://translate.googleusercontent....?id=13&usg=ALkJrhhE_17XSILWeyPw-u3dw0sBj7PTXg

The software that it comes with is nice but does not list a SINGLE chip that I have found on any arcade hardware. It's all mostly motherboard BIOS stuff. What is a good software to use with this programmer that will support chips such as TMS and HN?

Also, I am a n00b at this EPROM thing but am trying to learn so let me know if I am not making any sense.
 
Flash memory is programmed at Vcc for that device....1.8V, 3.3V, 5.0V

Older eproms need a seperate program voltage Vpp... 12.5V, 18V, 21V


So even if that your machine is pin compatible with some of those older
eproms it won't supply the higher voltages needed to write them.
 
Flash memory is programmed at Vcc for that device....1.8V, 3.3V, 5.0V

Older eproms need a seperate program voltage Vpp... 12.5V, 18V, 21V


So even if that your machine is pin compatible with some of those older
eproms it won't supply the higher voltages needed to write them.

Darn. I guess that's what I get for being a n00b at this. Thank you for the useful information.
 
Flash memory is programmed at Vcc for that device....1.8V, 3.3V, 5.0V

Older eproms need a seperate program voltage Vpp... 12.5V, 18V, 21V

So even if that your machine is pin compatible with some of those older
eproms it won't supply the higher voltages needed to write them.

In addition to programming voltages, there's another difference you should be aware of. Flash devices can be erased electrically by a programmer. Most EPROMS, on the other hand, must be erased using a UV eraser. Just another FYI. So unless you plan on buying new or already-erased-used EPROMs, you'll also need to get a UV eraser device.
 
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All EPROMS, on the other hand, must be erased using a UV eraser.
Fixed that for you. :)

If you can erase it without UV, it's an EEPROM or FLASH memory.

Although, there are some EPROMs that can't be erased at all, but those barely count... To save costs, while still producing easily programmable ROMs, there are some devices that use the same die as a normal EPROM, but are packaged in opaque plastic chip packages. They are electrically identical to an EPROM - but can't be erased, since they're sealed up. They're called OTP - One Time Programmable EPROMs. They're electrically not the same as PROMs - so they're still *called* EPROMs, despite the fact that they can't be erased. You find them a lot on computer hardware, video cards and the like. They'll have the same kind of EPROM part number - 27C512 or something, but they're plastic chips.

So unless you plan on buying new or already-erased-used EPROMs, you'll also need to get a UV eraser device.

You need an eraser. Don't think you'll just buy "pre-erased" ROMs, you'll make mistakes, you'll also really want to erase your own used ROMs. Now, you don't necessarily *need* your own eraser, provided you have access to one. I built a really big one years ago, it can erase 20 or 30 chips at a time. A friend of mine lives close by, and while he doesn't own an eraser, he really doesn't need one, since he just brings over a box of ROMs to erase every time he comes over.

-Ian
 
I always thought an OTP EPROM and a PROM were the same thing.. How do they differ?

OTP EPROM programs like an EPROM... uses voltage pulses to move the silicon gate structure. You are supposedly able to bombard them with high concentrations of x-rays to erase them if you wanted. ;)

PROMs have special fuses that are blown with programming pulses. Once programmed you can't do anything else but blow more fuses which renders them virtually useless.

Now, you didn't ask about Mask ROMs, but for the sake of completeness: Mask ROMs are made at the factory. They have a special mask used when constructing the chip that constructs the 0s and 1s on the chip. No programming involved other than creating the mask used to layer the deposits on the chips to assemble the memory cells.

RJ
 
I purchased an EPROM eraser at the same time as this programmer but it should be here in the next few days. I just did not know about the voltage thing. :/
 
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