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SiriusHardware · 29th Nov 2018, 8:38 pm

Nice diagram!

Actually, the simplest way out would be to make the last finger +5V instead of 0V, and the second last finger Reset. There are arguably good reasons not to have unlimited +5V on that edge connector though, as the edge connector is not keyed / position limited and one slip / senior moment could see hard +5V ending up where it should not be.

I don't think there are any pre-existing or historic peripherals which ever used those two 0V connections, because the external keypad doesn't need 0V.

29th Nov 2018, 8:38 pm	#123
SiriusHardware Dekatron Join Date: Aug 2011 Location: Newcastle, Tyne and Wear, UK. Posts: 11,560	Re: MK14 schematic revisions Nice diagram! Actually, the simplest way out would be to make the last finger +5V instead of 0V, and the second last finger Reset. There are arguably good reasons not to have unlimited +5V on that edge connector though, as the edge connector is not keyed / position limited and one slip / senior moment could see hard +5V ending up where it should not be. I don't think there are any pre-existing or historic peripherals which ever used those two 0V connections, because the external keypad doesn't need 0V.