Plugging in ARM-USB-TINY-H stops target device?

[tprk77]

I'm working with a STM-E407 dev board and the ARM-USB-TINY-H programmer. I've successfully programmed a little "heartbeat" program with ChibiOS to blink an LED.


I've noticed that when I plug the ARM-USB-TINY-H programmer into my computer, the LED stops blinking. It seems the device has stopped. Pressing the reset button has no effect. (Maybe it's being held in reset?) When I unplug the USB cable, the LED starts blinking again. I can only get the device to run while plugged into the computer by starting OpenOCD.

So anyone else run into this? Is this expected? I would like the device to run all the time, even if the programmer is connected to a computer. Is that possible?

I've been searching for an answer but I haven't found anything.

I would appreciate any help! Thanks!

[JohnS]

It's to do with the state of the signals - not to mention any noise when you plug it in.

You can choose the state of each but presumably have not done that as yet.

I guess a start would be to check each before plugging in and again after or better watch each as you plug in.

John

[tprk77]

I'm not sure I totally follow. When you say check the signals, you mean hook up a logic analyzer to the reset pin? I could probably do that but I was hoping for a simpler answer.

So I'm guessing my current situation is unusual, and this behavior isn't normal?

Do you think this has something to do with the code running on the device? That would be a good clue. (I was thinking more like a setting on my computer, or even the programmer, but maybe that makes more sense.)

[tprk77]

You can choose the state of each but presumably have not done that as yet.

Forgive my ignorance, I don't know what this means. What are these signals, and how do I set them? I searched the user manual for the ARM-USB-TINY-H, but I didn't see anything there. Help, please?

[JohnS]

JTAG signals.

John