Graphics_demo at 4mhz?

parts-man73

I wired up a RCA type jack to my propeller today with the appropreite resistors.
560 ohm to A15
270 ohm to A14
560 ohm to A13
1.1K ohm to A12

I loaded "Graphics_demo into my eeprom and took it upstairs to my TV and plugged it in. Pressed the reset button and sat back to watch the show, but all I had was a blank screen.

Well... I have 3 questions-

#1 - Can this be run with a 4mhz crystal. This is all I have currently. My local electronics store has a very limited selection, nothing in the way of crystals. I had a few 4 mhz Crystals laying around so I used that. I changed the _xinfreq to 4_000_000 and most programs have run fine. But I'm thinking this may be the reason this program isn't running properly.

#2 - Is a mouse required to run this program? I know it takes inputs from a mouse if one is connected. But is it required?

#3 - is the program set to use pins A12-A15?

Thanks in advance for the help,
Brian

Mike Green

1) You have to change one line in the graphics_demo program. Near the beginning, there's a constant declaration for _xinfreq. This is the crystal frequency and it's set to 5MHz. Change the 5_000_000 to 4_000_000 and recompile and reload. It should work. The TV video driver is designed to adjust its parameters according to the value of _xinfreq. The version distributed with the Propeller Tool is set up for video. If, for some reason, you have an earlier version, it may be set up for RF broadcast instead. If you're curious, look at the parameters (tvparams) near the end of graphics_demo.spin and the detailed explanatory comments near the end of tv.spin.
2) It will run without a mouse.
3) It is set to use pins 12-15 by default.

parts-man73

_XINFREQ was changed to 4_000_000, still no video. After I posted my original question last night, I also tried the TV terminal demo. Still no results.

parts-man73

Just doing some more testing tonight. Perhaps my propeller is dead? I just tried Blinkled.spin and I get no blinking LED. I'm got power to all the right spots, and ground to all the other right spots. Providing about 3.6 volts to my circuit. Double checked that my LED was in right. The Propeller Tool will verify it's connected alright, and I can load RAM and load EEPROM, and it loads the eeprom, and then verifies it. but no blinking LED.