Video on the Propeller

donnpangy

········· I am using the VGA_Text.spin, and I have some monitors that will not show any video. I have 4 different propeller boards. If I shoot video out of 2 different propeller demo boards, it seems to work on any monitor. If I shoot video out of the propeller proto board or my own board, it does not work on all monitors. I can get it to work if I shoot the video out of the propeller proto board, and run that through a KVM unit. It then runs on all 4 boards and on all monitors.

········ Do I have some kind of a termination type problem. I copied the video layout of the propeller demo board. I did not include the LED's and their 240ohm resistors. Could this be a problem? Can I add additional resistors on my board to get past this.

········· What can I do to my board so that all monitors work from it?


thanks so much,
Don

Mike Green

Some monitors are very fussy about the horizonal and vertical scan frequencies you're using and simply won't lock onto the sync pulses produced by the Prop.· It's not a matter of signal levels·and what's between the Prop and the monitor.· One of the VGA text drivers is for "high resolution" displays and has 3 blocks of constant definitions for different display sizes (like 64 x ?? or 80 x ??) and I have one LCD monitor that just won't lock onto one of the display sizes.

In terms of resistor values, look at the Protoboard + Accessories Kit schematic.· It shows the proper resistor values for VGA·without the LEDs and their resistors.

donnpangy

········ Thanks Mike for the info on the video. It is just strange that the same code works consistantly on the prop demo boards, but never on the prop proto board (unless i feed it through the KVM unit).

······· Mike, you seem to know a lot about video. Is there another hi res solution, other than this VGA_text.spin, that only uses 1 cog for video? I am starting a project and it isn't to late to change this yet.


······· Thanks so much
Don

Kye

Try this out,

It will be released in the Obex soon but I havn't got arround to it.



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Nyamekye,

donnpangy

Thanks Nyamekye,
I will take a look at it tonight. The 3D tiles code look interesting.
Thanks so much,
Don