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14700RE: Membership Card Serial Terminal Connection?

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  • wheagy2000
    Jan 19, 2014
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      Quick follow up to this...I double checked my wiring and toggled in the 'Walking Bit' demo to be sure the original RAM and MC is working as it should be.  The demo program worked fine and the wiring looks ok to me but I could be overlooking something just because I've been staring at this for so long.

      I threw a short video of the demo running as well as a few pics of the wiring.  If you feel so inclined, feel free to take a look and see if you can spot the error.  


      On the ROM, note that pin 27 is connected to 28.  Pin 20 goes to the resistor. which then connects to the Drain of Q2.  The other end of the resistor goes to P2 pin 3.  Q2 Source goes to Q hole 4.  Q2 gate is the red wire coming from Q2 going through the board below C2 and connecting to Q1 Source (connection 3).  ROM pin 1 goes to P3 pin 6.  ROM pins 1, 20 and 27 are not connected to their corresponding RAM pins.  Remember that I am using a 28C256, so pins 1 and 27 are switched.  There is continuity between the ROM and the RAM on all pins except 1, 20 and 27.

      Any additional suggestions are appreciated.  I'm running out of ideas.



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