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BR shield short? - Printable Version

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BR shield short? - usherman20 - 04-30-2021

Hi all,

I'm currently playing with my new CU and BR boards. I am running into a strange issue though: I can program the bare CU board fine, but cannot upload when the BR board is mounted. I uploaded the counter example and the builtin leds blink fine. I also have the IO shield. The IO shield example program works as expected, and I can program with the IO shield mounted. Trying to program the CU with the bare BR board fails with this error:

Extended device string lenght is 0xff. This is likely an error. Ignoring...
com.alchitry.labs.hardware.usb.ftdi.Mpsse$MpsseException: Flash ID was 0xFFFFFFFF expected 0xEF401600
    at com.alchitry.labs.hardware.usb.ftdi.LatticeSpi.flashReadId(
    at com.alchitry.labs.hardware.usb.ftdi.LatticeSpi.writeBin(
    at com.alchitry.labs.hardware.loaders.CuLoader.program(
    at com.alchitry.labs.hardware.loaders.ProjectLoader.load(
    at com.alchitry.labs.project.Project$load$1.invokeSuspend(Project.kt:1297)
    at kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith(ContinuationImpl.kt:33)
    at kotlinx.coroutines.scheduling.CoroutineScheduler.runSafely(CoroutineScheduler.kt:571)
    at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.executeTask(CoroutineScheduler.kt:738)
    at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.runWorker(CoroutineScheduler.kt:678)
    at kotlinx.coroutines.scheduling.CoroutineScheduler$
Both pins D36 and D39 (config reset, reset) are high. One further complication - if I mount the BR board on the CU while the CU counter led blink program is running, it continues to run fine (and probing the led pads on the BR match the lights fine). However, if I remove power and plug it back in while the BR is mounted, the loaded program _will not run_. Instead, I only see the on board leds shining very dimly. I don't feel any obvious hot spots in the board to indicate shorts, and I've probed 3.3V, 5V, and Gnd for shorts, and come up with nothing. Any other ideas??
Thanks, Jarrett

RE: BR shield short? - alchitry - 05-18-2021

Sounds like a short on the JTAG/configuration pins. Contact SparkFun for a replacement.