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Timbucus · 24th Apr 2019, 10:14 pm

Looking at my board from Martin it follows the schematic

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so D0 to D7 are actually on pins A18-A25. NRDS is on A28 and NENIN is on A31 with VCC on A32 under FL1

The spares are A26, A27 and A29/A30

Here is a closeup:

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and a photo of the bottom of martin's unpopulated clone - the only pin that connects on the top of the PCB is the Reverse Pages pin B15 that emerges on the Via in the bottom left up to the OR gate out on IC1. So all the traces can be seen and the bottom right is IC16 and the Data lines can clearly be seen clustering towards it. I also attach a photo of how I intend to connect them and still leave the option of a memory shim board - or even a backplane if I can get enough connectors...

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SH so is your VDU board different? Martin has a photo on his site with both an original and his clone side by side so maybe there are different revisions?

24th Apr 2019, 10:14 pm	#169
Timbucus Octode Join Date: Mar 2019 Location: Barry, Vale of Glamorgan, Wales, UK. Posts: 1,363	Re: MK14 schematic revisions Looking at my board from Martin it follows the schematic so D0 to D7 are actually on pins A18-A25. NRDS is on A28 and NENIN is on A31 with VCC on A32 under FL1 The spares are A26, A27 and A29/A30 Here is a closeup: and a photo of the bottom of martin's unpopulated clone - the only pin that connects on the top of the PCB is the Reverse Pages pin B15 that emerges on the Via in the bottom left up to the OR gate out on IC1. So all the traces can be seen and the bottom right is IC16 and the Data lines can clearly be seen clustering towards it. I also attach a photo of how I intend to connect them and still leave the option of a memory shim board - or even a backplane if I can get enough connectors... SH so is your VDU board different? Martin has a photo on his site with both an original and his clone side by side so maybe there are different revisions?