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Found these inside a non-working 71B
03-12-2018, 11:50 PM
Post: #53
Dave Frederickson Offline
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RE: Found these inside a non-working 71B
I'm a bit confused by the daisy-chain diagram above. The "main 5 chips" are all daisy-chained, out to in, but according to the schematic, U5, the ROM, has it's DOUT unconnected and VDD is connected to DIN on both U5 and U6, the Port(0.1) RAM. Can you clairfy?

Dave
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RE: Found these inside a non-working 71B - Dave Frederickson - 03-12-2018 11:50 PM
What's U10? - Dave Frederickson - 03-15-2018, 03:43 PM



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