Testing multiple SPI devices

Now I moved on to test 2 EEPROMS, with the following statements.


fttest.TestDemuxEeprom(mcp23s17SubAddress = 0, eepromDemuxAddress = 1, testStartAddress = 0x0123, testWriteDataByte = 0x3b)

fttest.TestDemuxEeprom(mcp23s17SubAddress = 0, eepromDemuxAddress = 0, testStartAddress = 0x0123, testWriteDataByte = 0x3b)

I tested with 0, 1, 2 EEPROMS plugged in and found results OK.

Then I plugged in the GPi, and strange thing happens.  The program seems confused and says GPi a good EEPROM!

I now have a feeling that there is something wrong with my 74HC32 OR gate based demux design.  Perhaps I should try some other SPI devices.

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