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Open Bench Logic Sniffer / Capture troubles
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?