stm32f10x Learning Note 9 (solve Jlink problem) __ Embedded system

Today when playing the development Board accidentally downloaded a problematic program, and then tragedy. Unable to burn the program into the chip. Every time you want to download the program, the following two error dialog boxes pop up.

The message window then displays the following error message.

Jlink Info:
------------
dll:v4.15n, compiled June 19:55:09
Firmware:j-link ARM V8 compiled May 20 20 17:07:46
hardware:v8.00
s/n: 24446459 
Feature (S): Rdi,flashdl,flashbp,jflash 
 
* Jlink info:could Not measure total IR len. TDO is constant high.
**jlink warning:no matching core found.
* Jlink info:could not measure total IR len. TDO is constant high.
* Jlink info:could not measure total IR len. TDO is constant high.
* Jlink info:resetting target using RESET pin
* jlink info:halting CPU core
**jlink warning:received 0 as Cor E Id.
Jlink error:could not find supported CPU core on JTAG chain Bad
JTAG communication:write to ir:expected 0x1, go T 0x7 (TAP command:2) @ off 0x5.

Baidu a bit, did not find any useful information. Still have to find a way to solve their own. First of all, my jlink and STM32 chips are unlikely to be so bad. Most of the software involved in the burning of some problems, occupy the corresponding IO leg, resulting in the inability to use jlink communication. Then find a way to keep the wrong program running. STM32 in the bootloader, switch into the bootloader can be. The specific method is to select the boot mode by BOOT1, BOOT0 two jumpers.

Power off, change jumper, power back on, enter bootloader mode. Download the new program with Jlink and download it successfully. Again power off, the jumper back to the power, all normal. Solve the problem.