On 08/19/2016 04:52 PM, Ethan Dicks wrote: > On Fri, Aug 19, 2016 at 10:37 AM, David Wood <jbevren@gmail.com> wrote: >> Is anyone familiar with what -5v is used for on PETs? > > Negative bias voltage for the 4116 DRAMs, a few dozen mA, IIRC. > > (if you have socketed DRAM and..) if you did the pinballer hack of > modding 4164s for use in 4116 sockets (lift out the -5V pin from the > socket, and run a jumper over the top of the chip to the high address > bit are the steps from memory), you might not require -5V at all. The > schematics are out on zimmers.net and shouldn't take long to verify > that's the only use. The 4164 don't like +12V, so there is a bit more rewiring necessary. Also, not all 4164 use a 7Bit refresh but some want 8 Bit. If you use them as 4116-Replacement, that shouldn't matter, but I'm not 100% sure. Gerrit Message was sent through the cbm-hackers mailing listReceived on 2016-08-21 18:00:03
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