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Add and Wire the Second Header to the Membership Card CPU Board

This is the worst part of the build. The Olduino needs the N0, N1, N2 I/O selection lines along with TPB and /MRD. I bring them up with a second female header which is superglued to the outside of the main one – see below. To keep things lined up during the install I use something like a double row of male headers or the olduino board to position the new header and hold it in place. The solder tails of the headers are bent outward 90 degrees in this example.
14-09-17 topview

On the bottom of the board the N0-N2 headers are soldered to the 1802 pins 19-17 respectively. Next is /MRD which goes to pin 7, and finally TPB which goes to pin 33.
14-09-17 revb

On the newer CPU Boards, the N0-N1 lines have access points below the CPU which I have used below. In this image you should ignore everything except the first 5 header connections. The others relate to using a 74HC132 for the clock and bringing the clock out to the header for some unrelated experiment.
14-09-17 revg

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