STM32 Nucleo-H743ZI2 VCP Port / STLINKV3

[Thomas L.]

Hi

I am currently evaluating the STM32H7 family on a NUCLEO-H743ZI2 board. I am having troubles with the UART. I checked the schematics for said board and it shows that the STLINKV3 on that board is connected to USART3 on the STM32H743. So I created a new project with a blinking LED (works as expected) and the USART3 in asynchronous mode. I'm periodically (each second) writing out "Hello World" via USART3 (blocking mode) and I can trace the signal up to the output of U1 (a level shifter which shifts from 3V3 to 3V3, yet a different domain) but I don't see anything in the virtual com port which is created when I attach the device to my PC. I'm using PuTTY with 115200 8N1 settings (I also configured these settings in CubeMX).

Is there anything I'm overlooking? Is the COM Port feature actually working? I haven't found an example in the STM32Cube Repository which uses the VCP on the STLINK.

TLDR: Can output characters via USART3 to VCP of STLINKV3 but don't see any arriving on the PC side

[B166ER]

I have exactly the same issue with this board. all other boards work fine.

any news on this matter ?

[Tesla DeLorean]

News looks to be only you TWO in the last SIX months have this issue.

Board is working fine for me, data comes out of ST-LINK VCP, but I'm not using CubeMX.

Check the clocks, and that the compensation cell is enabled.

As I recall a couple of pin changes on the ZI2 relate to LEDs, QSPI and ETHERNET​

[Tesla DeLorean]

Here using USART3 (PD8, PD9 with AF7) running at 115200 8N1

NUCLEO-H743ZI2 DEBUG Demo
 
Core=400000000, 400.00 MHz
CPUID 411FC271 DEVID 450 REVID 2003
Cortex M7 r1p1
C0000018 20000F50 00000000
10110221 12000011 00000040
FPU-D Single-precision and Double-precision
STM32H7xx
HCLK=200000000
APB1=100000000
APB2=100000000
PLL1_P_CK=400000000, 400.00 MHz
PLL1_Q_CK=200000000, 200.00 MHz
PLL2_P_CK=0,   0.00 MHz
PLL2_R_CK=0,   0.00 MHz
E000ED08 SCB->VTOR
Infinite Loop...

[B166ER]

hello,

I have tested your image on three different H743ZI2 boards, but I never receive any message on the VCP.

the LEDs are blinking however.

all other STM boards I have give me output over the VCP.

this is crazy... I am thinking if all three boards are broken...... but this is highly unlikely

do you have a picture of your board of FRONT and BACK ?

I want to compare the solder bridges and so on if there is any physical difference.

kind regards

[Tesla DeLorean]

Will see what I can do.

SB5 and SB6 should be ON, SB4 and SB7 OFF

Jumpered for 3.3V operation JP5

Rev C board

Will see if I can get the angle, focus, lighting better

Alternate would be LPUART1 via SB8, SB9, SB18 and SB12, SB34, SB66, SB18

[Tesla DeLorean]

[Tesla DeLorean]

There is some flux near SB7, suggesting it might have been removed (not by me)

[Tesla DeLorean]

SB5 looks OFF, so using the level shifter.

Do you have a shield plugged in?

SB12 and SB19 should be ON signals at chip

SB3 SB4 OFF

SB18 SB66 OFF

SB8 SB68 ON

SB9 SB34 OFF