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Topic: Capture troubles (Read 1439 times) previous topic - next topic

Capture troubles

Well I just lost a post I spent like an hour chronicling my tribulations in, so I'm gonna try and make this short.

Plugged in my OBLS for the first time today, I'm just trying to follow the first example in the documentation, and after much frustration with triggering not working I gave up on UART and decided to start as simple as possible with PWM. Just like the first example in the documentation, I have MISO to GND, and MOSI to pin 7. I've tried every combination of the mask/value checkboxes, but seeing as the OBLS just doesn't seem to register the PWM input, it either never triggers, or triggers instantly and gives me a blank trace. I accidentally discovered that a trace would appear if I touched the MOSI line, however it didn't correspond to the PWM frequency, so I was confused. Eventually, I found that it had nothing to do with the bus pirate, as I could remove it entirely, and get the same trace out (see attached) just by jumping the pins with my thumb (as long as I don't touch GND).
Another thing, my ARM led comes on when I plug it in, but not TRIG. I believe this started after I tried to update the firmware, which I had issues with as well. Basically I had the problem where I couldn't get the bootloader updated because it decided the device wasn't connected anymore after flashing the FPGA, but I got around it by trying to flash the FPGA with the older version which threw an error and dumped it into bootloader mode without disconnecting it. Then I was able to install the demon core 3.0 FW, run the updater again, and flash the FPGA with demon core 3.07.
I feel like I'm just being stupid about something, but I don't get why the PWM wouldn't register at all, when I can measure the difference with a multimeter just fine.
Help a noob out?