View Full Version : Propeller lost on com8

12-24-2009, 08:31 AM
I just recently soldered up a propeller chip for a custom project I'm working on. It runs programs just fine, but I'm having trouble with loading the EEPROM. When I hit F11 to load the EEPROM, it looks like its working. After a second I get an error "Propeller lost on com8". I'm just trying to figure out if this is a problem with my prop chip, or my EEPROM. Any ideas? Thanks for looking.

Mike Green
12-24-2009, 09:20 AM
Probably neither. It could be a problem with your power supply or a problem with your PC, your USB driver, your USB to serial adapter, or your cables.

If it was a problem with your Prop chip, you wouldn't be able to run programs. If it was a problem with your EEPROM, you would get a specific error copying the program from the RAM to the EEPROM which occurs at the end of the download process.

12-24-2009, 10:25 AM
I can save programs to the EEPROM onto another board. That means that my PC, USB driver, and cables should be good right? If it is a power supply problem what do I need to look for? I measured the voltage at the EEPROM while I'm trying to load the EEPROM and I notice no change in voltage. Is there something else I need to look for? Thanks

12-24-2009, 01:37 PM
By hitting F10, I think you can load the program into the Prop without loading it into the EEPROM, so that's one way to deduce the source of your problem, but I think you already know that.

I notice I will often get the same problem you're describing when my PC is running virus scans, etc. in the background, a process which my laptop seems to do a lot of. So loading up an EEPROM simply becomes a dreary task of hitting F11 over and over until I happen to hit a sweet spot in the background processing that doesn't mess up the EEPROM loading process. For me, it usually takes about 6 tries to get through. It seems that when my laptop is making a whizzing sound, I have the least probability of getting the EEPROM loaded, so you might have to wait for your PC to complete a bunch of start-up housekeeping functions and reach Zen serenity before attempting an EEPROM load.

my 0.002 cents worth.