All,
I am using an LM3S1968 Evaluation board from TI. I installed the latest released version of uVision (4.23) from the Keil website. I installed the appropriate USB drivers that came on the Stellarisware disk that came with my evaluation board.
The problem I am having occurs when I am trying to download a compiled program to my evaluation board. The project that I have was able to "Translate" and then subsequently "Build" successfully without any warnings or errors. When I finally select "Download to Flash" and my evaluation board is connected directly to my computer's USB port, it shows the following:
Connecting: Mode=JTAG, Speed=600000Hz Erase Done. Programming Done. Verify OK.
After it shows this, the entire uVision applications freezes, and Windows reports it as "Not Responding". While still connected, I can reset the microcontroller, and it executes the newly downloaded code fine. The only way to get the application to start responding again is to unplug the USB cable, which then powers down the board. I experience the same behavior when I try and stop the debugger. It starts successfully, but will freeze when I try to end it.
The funny thing about this, and what I can't seem to figure out, is that everything works perfectly fine whenever I connect my board through a externally powered USB hub.
I'm not entirely sure what would be causing this issue and whether or not my evaluation board is causing the problem, or if it's the fault of the uVision software. Any help in debugging this issue would be much appreciated.
-Chris
"After it shows this, the entire uVision applications freezes, and Windows reports it as 'Not Responding'", "I experience the same behavior when I try and stop the debugger. It starts successfully, but will freeze when I try to end it."
I have noticed that uVision freezes as a normal condition when waiting for things to happen, while most proper applications would have a timeout and a progress indicator. I have also had uVision stop responding on a regular basis such that Program Manager intervenes. It seems that uVision does not handle common events and circumstances very well.
"The only way to get the application to start responding again is to unplug the USB cable, which then powers down the board.", "The funny thing about this, and what I can't seem to figure out, is that everything works perfectly fine whenever I connect my board through a externally powered USB hub."
Maybe your board is experiencing a brown-out due to your PC USB port not having enough current capacity? Based on the known behavior of uVision to unusual circumstances, I would be surprised if uVision can properly handle a target brown-out reset.