Jlink could not halt CPU during linking STM32F103VET6

[KUHAN JON]

Posted on September 09, 2017 at 04:35

Hello,

I have a trouble using STM32F103VET6.

I attached the reset and boot circuitary.

i have assembled three boards and tested.

Unfortunately, one of them was normal, but the others were not.

The trouble is as follows.

When i turned on the board, KEIL showed me 'Auto write protected device detected.........' and i clicked 'yes' to download the firmware.

But the board did not work normally.

I measured the voltage of NRST pin and BOOT0 pin after power on. The voltage of the NRST pin was 3.34V( power supply voltage is 3.29V) and of the BOOT0 is 1.7V.

But the voltages of normal board were 3.28V and 0.1V respectively.

I tried agian to link Jlink( i used SW 4-wire mode), but KEIL warned 'Jlink warning: CPU coild not be halted'.

But the normal board always works normally.

I really did not analyze this phenomenon. 

Help me to find the reason of this trouble.

Thanks. Jon

[Vangelis Fortounas]

Posted on September 10, 2017 at 23:26

Hi!

>>>> the BOOT0 is 1.7V.

from datasheet

0.28*(3.29-2)+0.8 = 1,16V

You are above of max input low voltage.

Means also  that boot pin's  internal resistance to VCC is ~10K. (abnormal for a CMOS input ) .. or some problem with power cirquitry of the board exists

First check if all VSS ,VSSA pins are connected to ground.

After check all the other power supply pins VDD,VDDA,VREF-,VREF+ if properly connected. Also check for 5V inputs to non FiveVoltsTolerant pins.

Regards

vf

[KUHAN JON]

Posted on September 11, 2017 at 02:27

Thanks, Vangelis.

I also have a doubt for the power circuit.

Yes, i will check all power circuitary and reply the result.

Thaks, Jon.