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08-27-2017 08:28 PM
I am using a custom board with EFM32PG12B.
I use Flash programmer that comes with simplicity studio. Once I load .bin, or .hex, it starts running right away(output messages was seeen from serial port, and LED flashing). However when I unplug JLINK and power off it, then power on it, it doesn't run(I can't see any output from serial port, nor LED flashing). What's wrong? Any hint will be appreciated.
Solved! Go to Solution.
08-27-2017 10:03 PM
Sounds very strange. I recommend try a very simple example like the blinky from Silabs first to see if this issue also happen.
08-28-2017 09:09 AM
I build a blink project with UART driver, and program it to flash.
After generate an external reset to RESETn pin, it starts finally. It can detect button press/release and then blink LED now.
But I find another "interesting" problem. If no JLink attached, UART doesn't work. If JLink attached, then UART works right now.
1. without Jlink attached, generate external reset to RESETn pin, it starts with LED blink, while no UART output (it should have some output like "\r\n\r\n/****************EFM32 Pearl Gecko example***********************/\r\n").
2. press button, blink stop
3. press button again, blink start again.
4. attached Jlink(only plug the cable to the 6-pin header), send enter key to serial port, it shows prompt "-> ". Press button, it shows "button press"
5. de-attached Jlink(only remove the cable from the 6-pin header), nothing can be seen from serial port whatever press botton or send any char.
I really have no idea... Can you please help me?
08-29-2017 04:07 AM
Usually when the uart only works when the debug probe is attached, the problem is a missing GND connection on the UART interface.