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Timbucus · 6th Jun 2020, 1:06 am

I think that is how I fried the '86 as I used 0xFF to enable all of Port A as outputs - because stupidly I could not work out what was happening using 0x01 only to enable into 0x0822 - by the way when you do that PA7-PA4 end up as Outputs anyway ... I was very confused.

(Edit: to clarify of course I had used a clip lead to link the connections so when PA1 went output it did just what you describe. The connection on the VDU PCB has been pulled out and bent up now like I did for INTR etc...)

Still I have learned a lot so £12 is a cheap lesson I suppose.

6th Jun 2020, 1:06 am	#57
Timbucus Octode Join Date: Mar 2019 Location: Barry, Vale of Glamorgan, Wales, UK. Posts: 1,364	Re: Mk14 vdu I think that is how I fried the '86 as I used 0xFF to enable all of Port A as outputs - because stupidly I could not work out what was happening using 0x01 only to enable into 0x0822 - by the way when you do that PA7-PA4 end up as Outputs anyway ... I was very confused. (Edit: to clarify of course I had used a clip lead to link the connections so when PA1 went output it did just what you describe. The connection on the VDU PCB has been pulled out and bent up now like I did for INTR etc...) Still I have learned a lot so £12 is a cheap lesson I suppose. Last edited by Timbucus; 6th Jun 2020 at 1:13 am.