Duanxx stm32 learning: Error no cortex-M device found in JTAG chain cause and Solution

I reported this error when I gave the stm32 program today. I searched the internet for a long time and found a reason and a solution. The online statement is as follows:

 

Cause:

Burned programsDisable the JTAG function.,JTAG interfaces are reused..

 

Solution 1:

Find boot1 and boot0, lower boot1 and boot0 to 3.3 V, and download a program through the serial port. This program does not close JTAG, and then you can normally re-use JTAG, set both boot0 and boot1 to a lower value.

 

Solution 2:

The JTAG port function can be restored when the chip code is erased. Start with -- segger -- jlink arm -- open J-flash AR (find the installed J-Link driver, I am using segger's jlink connector, installed with the v4.12 driver)-OK-then select the target option-connect-and then select eraser chip.

The above is very reasonable, but I have not tried the above method. I found the solution directly on the official website. The official website explains the following:

The preceding figure shows that the JTAG pin is occupied by programs and can only be regarded as "Debug interface is notworking". The preceding solution is to download programs through serial ports, which is troublesome. Solution on the official website:SWD download, See.

Note that after selecting the SW mode,SW device should be identified by a deviceOtherwise, the connection between the download tool and the stm32 is incorrect.

Duanxx stm32 learning: Error no cortex-M device found in JTAG chain cause and Solution