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SiriusHardware · 11th Nov 2020, 9:46 pm

With firmware FW692 and 200pF capacitors on A8-A11, I have left Charset running for some time, writing continually to each of these memory blocks.

02xx
03xx
04xx
05xx
06xx
07xx
0bxx

In each case the programme was left running for about 15 minutes. At no point were any unexpected writes seen.

I''ll probably now drop the capacitance down to the 'standard' value of 180pF and leave it at that, as I know that the low capacitance value threshold (below which problems appear) is somewhere between 100-150pF for my system.

Tim, if you get a chance can you also try yours with 180pF (or capacitors combined to make up that value) and then remove your RAM upgrade and make sure it still works with the 180pF capacitance?

11th Nov 2020, 9:46 pm	#884
SiriusHardware Dekatron Join Date: Aug 2011 Location: Newcastle, Tyne and Wear, UK. Posts: 11,575	Re: Mk14 vdu With firmware FW692 and 200pF capacitors on A8-A11, I have left Charset running for some time, writing continually to each of these memory blocks. 02xx 03xx 04xx 05xx 06xx 07xx 0bxx In each case the programme was left running for about 15 minutes. At no point were any unexpected writes seen. I''ll probably now drop the capacitance down to the 'standard' value of 180pF and leave it at that, as I know that the low capacitance value threshold (below which problems appear) is somewhere between 100-150pF for my system. Tim, if you get a chance can you also try yours with 180pF (or capacitors combined to make up that value) and then remove your RAM upgrade and make sure it still works with the 180pF capacitance?