EEPROM

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Floopy
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EEPROM

Post by Floopy »

I'm wondering if anyone knows how to burn EEPROM chips. If so how can I hook one up to the VIC or C64, I'm fairly new to 80's electronics and there. I know EPROM exist also but I don't want to constantly have to use a UV light to erase.
Also which is cheaper?
Anyway if you know either way I would like to know.
Thank you :D
-Floopy
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srowe
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Re: EEPROM

Post by srowe »

By "hook up" do you mean running code in an EEPROM on the VIC? It's just a memory device, you connect the address & data lines to the correct pins on the cartridge port. Depending on the size of the device you may need some other chips for Chip Select logic.

You may also be able to directly program an EEPROM from the VIC, although when I tried I couldn't get the timing right to lock and unlock the device. My cheap USB EPROM programmer can handle EEPROMs though so I didn't investigate further.
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Floopy
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Re: EEPROM

Post by Floopy »

Well that's what I meant by hook up.
Other thing what EPROM programmer do you use? Also what type of EPROMs would work with the VIC or C64?
-Floopy
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srowe
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Re: EEPROM

Post by srowe »

I have a TOP853, it was really cheap a couple of years ago but there aren't drivers for recent versions of Windows and it appears to have been replaced with the TL866CS. Just search for these on eBay. They both support a large range of 27 series EPROMs and 28C series EEPROMs.

Pretty much any parallel EEPROM/EPROM will work with a VIC or C64. If it is less than 8K you can connect it directly to the lines on the cartridge port using one of the BLK lines for the Chip Select. If it is larger than 8K you need some extra logic to combine multiple BLK lines or to select different banks of the device.
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srowe
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Re: EEPROM

Post by srowe »

Here's my home-built ROM/RAM board (with an 8K EEPROM). Most of the address and data lines are the same across the different chips, I have headers for pins related to select, read/write etc so I can tinker with various different devices.
20170609_214151.jpg
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Floopy
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Re: EEPROM

Post by Floopy »

Thank you very much I will see what I can try!
:D
-Floopy
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