VOGONS


First post, by Lostdotfish

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Does anyone remember these? I used to use one on my DFI nF2 Ultra B when overclocking using unstable modded BIOSes. It saved me more than a few times.

Just kind of wondering if there was any call for these devices in our retro hardware circles? Was thinking about trying to get one and reverse engineering the schematic of it.

Reply 1 of 3, by nhattu1986

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i think they are just simply connect all the pin minus the chip enable pin which can be control by a 3 pole switch to select which chip are going to be active.

Reply 2 of 3, by Lostdotfish

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nhattu1986 wrote on 2025-02-18, 12:30:

i think they are just simply connect all the pin minus the chip enable pin which can be control by a 3 pole switch to select which chip are going to be active.

No they use a 74HC00 NAND gate to switch between the main BIOS and the backup - so there must be several pins that need to be swapped between chips to make this work. It's a quad NAND so there will be 2 pins being redirected

There is then a simple 2 position switch to swap between the 2 inputs on the 74HC00.

Nice thing about these is they essentially turn any motherboard into a BIOS programmer. Bad flashed a board? No worries, grab a spare board and piggy back the bad flashed chip on it and reflash.

Reply 3 of 3, by Horun

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Lostdotfish wrote on 2025-02-18, 13:04:

Nice thing about these is they essentially turn any motherboard into a BIOS programmer. Bad flashed a board? No worries, grab a spare board and piggy back the bad flashed chip on it and reflash.

A safe way to hot flash w/o worrying about effing up the motherboard or eeprom, nice feature.

Hate posting a reply and then have to edit it because it made no sense 😁 First computer was an IBM 3270 workstation with CGA monitor. Stuff: https://archive.org/details/@horun