video problems of a newbie

neko

I'm pretty sure that this has been gone over before but I went back about twenty five pages of posts and did not find anything that helped. Having seen that it goes back about 150 pages (and not wanting to go through it all)·I decided to face the possible scorn of some for bring up a previously gone over subject. Anyway, I have both the Propeller demo board and protoboard (installed the accessory kit) and I can't get·video out of either board, TV or VGA, except with the demo board and TV Terminal Demo v1.0 sample program. I looked at the code of the sample programs and they seem to approach creating·video output a little differently. But being unfamiliar with the language I'm not sure how some of the values are being obtained. It seems as though if you are able to specify the start pin for video at 12 it runs fine for the demo board. The protoboard having only VGA video port at this time, I am lost with that one since I can get no·VGA output from either one (monitor says no signal).

I'm assuming that the sample programs are meant to work with the demo board and/or protoboard·with no modifications so the programs will point to the correct starting pin. Am I wrong on this?

For the demo board since the VGA out is connected to the LEDs I figure since the LEDs work there should be signal going to the VGA port. There is continuity from the before the resistors to the VGA port so I believe my soldering is okay.

Any help would be most appreciated.

·

Mike Green

The I/O driver is different for VGA. The TV Terminal Demo works for TV only. There are different demos for the VGA drivers. Have a look at vga_hires_text_demo.spin and the associated vga_hires_text.spin driver. There are other VGA drivers and demos included with the Propeller Tool and some others in the Propeller Object Exchange.

neko

Thanks, Mike, for the reply. Sorry, that I mixed the two video problems together. Trying to two birds with one stone. I understand that the TV terminal demo works for only TV and did try to run it using a VGA monitor. I ran the sample·programs for·TV·included with the Propeller·Tool·and tried it on both an LCD and CRT TV, no luck. I remember having success with the CRT TV using an SX28 chip and a similiar video circuit as the Propeller's so I figured I'd change the type of TV just in case because the SX video circuit worked better on the CRT TV. I·ran the VGA sample programs and connected to my computer monitor and a projector but to no avail.

I'll take a look at the Propeller Ojbect Exchange and see if those work.

Thanks!

neko

Again, Mike, thanks! I was mixing up the driver programs and demo programs. So, all is well in Propeller-land. Well, almost... has anyone experienced Propeller Tool locking up if you boot your computer with the Propeller clip attached? It happened four times until I took the clip off and it works fine now. Strange.

deSilva

neko said...
I was mixing up the driver programs and demo programs. .

This is a common problem: You change here and there and press F10, and - bingo - doesn't work any longer!
This happened - yes! - even to deSilva many times, until, one day.....

As there is no such thing as a "main program" you can easily include a "Module Test" into all your sub objects, similar to the excellent usance from Python. Just add a "PUB demo" as a first method, doing some easily recognizable things, best a feature demonstration of course. The SPIN overhead is minimal!
And don't forget the crystal settings if needed (for video oder serial)

neko

Thanks, deSilva. The terminology in Propeller language is very different than what I'm use to so when you include other files or libraries under OBJ or object it's hard to get a grasp of (language not so much concept). I guess it was harder to jump from blinking LED to video than I thought.

Mike Green

neko,
There was a thread about this lock up. It occurs if the PropClip (or any USB-based interface) is attached to the Propeller, but not powered from the USB bus. There's a sneak path for the transmit data line from the Propeller through the FTDI chip, back to the reset line if there's no power for the FTDI chip. It only happens some times ... not with all FTDI chips, not with all PropClips, etc. There were a couple of suggestions for fixes, but mostly to either pull the PropClip off if you're not using it or keep it powered.

neko

Mike,
Nice to know. I have another USB to serial interface that goes to my RC transmitter that I leave connected all the time (with and without the transmitter) and have no problems with it. I wonder if it is specific to the FTDI chips? Well, like you said it happens sometimes. Thanks for the info! I'm leaving it off until I need it.

BTW - I really appreciate all the help from everyone. I know there are times when I seem to not know a thing about what I'm talking about (which is not too far from the truth) but all of you have been very patient and generous with your advice.