Tsunoni
Student
I want to switch between two 27C64 eproms. Could this safely be done with a dpst switch that disables or enables the VCC pin and all the other pins are connected or even piggybacked?
Switch between 2 eprom chips
- Thread starter Tsunoni
- Start date
Why not concatenate the files and write them to a 27c128, then use a switch to activate the highest address line (tie A13 pin 26 to either Vcc or gnd) instead? Cleaner than piggybacking.
Tsunoni
Student
I want to use the original rom chip and I already have a 27C64. Its a great option amd thanks for the info. Also i wowouldnt be ppiggy backing. I have 3 ZIF sockets that I plan on using. I want to put one one the board if it fits then put two on a bare pcb and make it plug onto the board so I can have it in a modular kinda format
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Tsunoni
Student
Sometimes the hard way pays off or i dont mind or like it. How do I do it the dirty way, no homo.
the "hard" way here is pretty impractical unless you route and print a pcb yourself, or find one already built. Something like this but for your size of chip. Otherwise you're going to run like 60 jumper wires connecting all the zif sockets up. Piggybacking would be simpler at that point!
When I want to dual boot program code (using the double-sized chip method), I try to find an unused dip-switch on the board and use that as my toggle since it's already connected to Vcc/gnd.
Highlighted in red since it’s hard to see
When I want to dual boot program code (using the double-sized chip method), I try to find an unused dip-switch on the board and use that as my toggle since it's already connected to Vcc/gnd.
Highlighted in red since it’s hard to see
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Tsunoni
Student
Yeah i know i plan on making my own circuitboard with a copper board and tthat ferrite solution or whatever its called. I have plenty left over from the last time i drew one up. If that for some odd reason wont work ill just make the 48 or so connections. I dont mind that either. So would I be abke to just toggle the vcc?
Tsunoni
Student
Is that safe to switch between the chips, by toggling on or off the ce, of one or the other chip, in a piggy backing style too?
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