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Slothie · 15th Sep 2021, 9:53 am

I was thinking about this last night, then I thought to myself that I shouldn't worry too much. The prototype MK14 I built previously had the same decoupling as the original MK14 (i.e. virtually none) and there was so much noise on the signals that it was hard to see the signal, yet it still worked. When I made the r1.2 board I made sure there was plenty of places for decoupling caps and the amount of noise is much less. Its worth taking sensible steps to improve signal quality but we're not going to be putting this gear into any flight computers or medical equipment

If I can reduce the noise I'm seeing that will be a good start.

As far as removing the white bar at the left of the screen, I cant see any simple way to do this without big changes to the OrtonView, or move to a different PIC. Personally I find the white bar is so far from the "active" content of the display in practice that I don't notice it, or at least it doesn't bother me. However I understand not everyone is so relaxed

If we can get it to work with the 16F877A or 16F887 that would be better as the 16F877 is getting rare and the whole point of the exercise was to make MK14 VDU software accessible. Sirius noted that we moved off the '887 because Karen found her programmer didn't support it for some reason, and the '877A caused glitches in the graphics mode for some reason. So it might just be a matter of moving to the '887 chip as they are essentially the same chip (I think the 887 has 1 more pin that can be used for I/o).

15th Sep 2021, 9:53 am	#507
Slothie Octode Join Date: Apr 2018 Location: Newbury, Berkshire, UK. Posts: 1,287	Re: Ortonview PCB I was thinking about this last night, then I thought to myself that I shouldn't worry too much. The prototype MK14 I built previously had the same decoupling as the original MK14 (i.e. virtually none) and there was so much noise on the signals that it was hard to see the signal, yet it still worked. When I made the r1.2 board I made sure there was plenty of places for decoupling caps and the amount of noise is much less. Its worth taking sensible steps to improve signal quality but we're not going to be putting this gear into any flight computers or medical equipment If I can reduce the noise I'm seeing that will be a good start. As far as removing the white bar at the left of the screen, I cant see any simple way to do this without big changes to the OrtonView, or move to a different PIC. Personally I find the white bar is so far from the "active" content of the display in practice that I don't notice it, or at least it doesn't bother me. However I understand not everyone is so relaxed If we can get it to work with the 16F877A or 16F887 that would be better as the 16F877 is getting rare and the whole point of the exercise was to make MK14 VDU software accessible. Sirius noted that we moved off the '887 because Karen found her programmer didn't support it for some reason, and the '877A caused glitches in the graphics mode for some reason. So it might just be a matter of moving to the '887 chip as they are essentially the same chip (I think the 887 has 1 more pin that can be used for I/o).