I am trying to use the JTAG ulink debugger to catch issues in communication in our USB driver on a MCBSTM32E board. The board is powered off the USB and if I run my code without the JTAG attached I can tell by my USB tester app that I have communication going on. When I hook up the JTAG and run the debugger I only hit my USB callback functions during the USB init.
I have the VUSB jumper set to GND and have tried many combinations of resets and reconnections of cables but I can't get the USB peripheral to behave normally when the JTAG debugger is running and power is being supplied over USB.
Am I out of luck?
Andrew; There are others more able to answer you post but let me ramble about what I have frequently observed. Running just about any USB target powered with the USB host and debugging with the uLink has caused me a great number of problems. Almost always, I have resolved this by inserting a self powered USB hub between the host and the target. Bradford
There are others more able to answer your post but let me provide a link to you.
www.beyondlogic.org/.../usb6.htm
These timeout periods are quite acceptable for even the slowest of devices, but can be a restriction during debugging. 50mS doesn't provide for many debugging characters to be sent at 9600bps on an asynchronous serial port or for a In Circuit Debugger/Emulator to single step or to break execution to examine the internal Registers. As a result, USB requires some different debugging methods to that of other microcontroller projects.
I got a powered USB hub and that has solved my problem, thank you!
Mark one for the good guys! I have never attempted to determine the cause and effect. High current or timing, I don't know. I just use the hub and continue with my main problem of debugging my "perfect" code. I get a lot of debugging practice! Bradford