It seems to go through the motions, downloading etc and when it is due to reconfigure itself, it disappears.
This is a new installation on a new laptop (previous computer worked ok).
Tried un-installing and re-installing uVision and Si8051F_uVision.exe driver.
Suggestions?
This is not uVision's fault. It's the debug driver you're using, it signals a lost connection to the device under test. Without a connection to the target, uVision exits debug mode and that's what you're seeing.
What debug driver are you using? Did you check for updates? What debug adapter are you using? If it is a self-made one, it may be worth thinking about getting one from the device's manufacturer. What board are you trying to debug, is it a manufacturer provided evaluation board or is it a custom board? If it is a custom one, did you check an official eval board? And how do you power your target? Did you check that you've a clean and stable supply? Did you check the DUT's reset pin and it external circuitry for being correct? Did you check the debug adapters cables?
BTW: Firmware can cause such observations as well. Better do not enter low-power modes during debug. This too may cause lost connections.
Rene, thanks for your response.
Debug driver SiC8051F_uVision.exe (v4.40 I think), downloaded it this morning to be sure it's latest. Removed previous versions first.
The adaptor is the Silicon Labs USB Debug Adaptor. Hardware is our own design using C8051F361 processor.
Target is powered from onboard PSU, 3V3. C2D is s shared IO line (P3.0) set as an output (with 1K pull up resistor). These have not changed from when it did work!!
www.silabs.com/community is, probably, a better place for this
it is c2ck that need a pullup
Have you checked if the vendor's own program/debug utility works OK?
If that fails, then it's clearly not a Keil issue ...
The C2D sharing should not be an issue, it's set to an output and it does not matter if this changes during programming.
I've tried a different SiLabs programmer and same issue. I don't have another PCB to try at present.
I've tried using the SiLabs programming utility and I can download, run/halt, disconnect/reconnect and re-download without issues.
There seems to me to be a uVision or uVision/driver setting issues?
Yes, it does sound like it.
As it's specific to the SiLabs kit, I'd second Erik's suggestion to post in the SiLabs forum.
Don't forget to link this thread, and to post a link here ...
Or, if you have a paid-for Keil licence, contact Keil support.
Similar behavior here, with uVision 5.26.2 and ARM MDK. When debugger starts and menus/windows rearrange, in ~ 1 case of 5-6 IDE hangs for while then silently dies. Since last week I work on a small laptop screen, I guess this bug is triggered by small screen size. Did not seen it with a large monitor.
-- pa
And I don't have any 3rd party add-on in uVision. Not Silicon Labs or anything. Debugger device is ST-LINK v2.