BLUEPILL STLINK V2 PROGRAMMER

Make a Stlink V2 programmer/debugger for STM8/STM32 using a STM32F103 MCU

Sometimes one needs a SWD programmer/debugger for a project but a commercial ‘board’ such as a Discovery, Nucleo or $5 - $20 Chinese clone programmer isn’t available, so it can be handy to build your own or use a cheap spare Blue Pill type board to make one.

Copyright

Licensed under the MIT Copyright.

Originally Posted by Mecrisp Stellaris

Installing STLINK on a STM32F103 MCU based board

Now referred to as The Board

Get the Stlink binary in the /files subfolder

Mini-arm Board

mini STM32F103C8T6-board

Electrically the same as bluepill but has a JTAG connector.

• connect JTAG connector from mini-arm to Olimex Tiny-H JTAG dongle
• plug Olimex Tiny-H USB cable into PC
• run flash-STLinkV2.J16.S4.bin.sh (STLinkV2.J16.S4.bin)

Other boards with a STM32F103

Such as the Bluepill etc

Flash STLinkV2.J16.S4.bin to The Board using your normal flashing method.

After flashing STLinkV2.J16.S4.bin

• reset board
• “dmesg” should show “STMicroelectronics STM32 STLink at ”

WARNING!

“st-info –probe” will FAIL because the firmware we flashed is obsolete, even tho it shows as a “STMicroelectronics STM32 STLink at ” above. This is not a problem as we upgrade to the latest STLink firmware in the next step.

Upgrading to the latest STlinkV2

There are no binaries available for the latest StlinkV2, to upgrade from the obsolete binary that is available online, a Java based ‘updater’ program made by ST is required.

Install the STlink Java ‘Updater’

• Get the following package stsw-link007 from the /files subfolder
• It’s Java and has packages for all the Linux distros, just follow the instructions
• Run “java -jar STLinkUpgrade.jar” for the GUI updater
• Plug The Board USB connector into your PC and run the Updater, it should fetch the latest firmware and flash it to The Board.
• The Updater will show that the existing FW version is “V2.21.S4” and what it will be updated to, mine was “V2J45S7”
• Reset board
• “dmesg” should show “STMicroelectronics STM32 STLink at ”

Note

The Updater WRITE PROTECTS the MCU, so the updated binary cannot be read and saved (to avoid all this Java based stuff). If the MCU is set to “unprotect” it just erases the Flash. That’s why there are no binaries floating around the Internet.

• Run “st-info –probe”

With no MCU connected, just The Board (no external target MCU connected) running stlink-V2J45S7 should produce something like the following output:

> st-info --probe

Failed to enter SWD mode
Found 1 stlink programmers
  version:    V2J45S7
  serial:     576b507151542723
  flash:      0 (pagesize: 0)
  sram:       0
  chipid:     0x000
  dev-type:   unknown

The Board is now updated and thinks it’s a Stlink programmer/debugger running the latest firmware.

Connect the target MCU header board to the new Stlink

Green STM32F051 UFQFPN32 header board: GREEN PILL

Note

You can use any STM32xxxx MCU here, just change the “Pins” list to suit.

Wiring

Five wires connect The Board to the target chip. Keep the wires as short as possible as SWD is very fast and long wires just won’t work. The usual short “Dupont Cables” will be fine.

STM32 Functions	Bluepill Target Board	Bluepill Stlink Board	Wire Colors I used
GND	Gnd	Gnd	Black
SWCLK	PA-14 (SWCKL)	PB-13	White
SWDIO	PA-13 (SWDIO)	PB-14 <-connect to-> PB-12	Grey
3.3V	N/A	3.3V	Red
N/A	5v	VIN	Red
NRST	7 (RST)	PB-0	Yellow

Testing that Stlink can “see” the target MCU is connected

> st-info --probe

Found 1 stlink programmers
  version:    V2J45S7
  serial:     576b507151542723
  flash:      131072 (pagesize: 1024)
  sram:       20480
  chipid:     0x410
  dev-type:   STM32F1xx_MD

Success!

Success!! the STlink sees the F0 Device connected !! compare this to the “st-info –probe” above with no MCU connected ?

The Board can now be used to flash target mcus using st-flash or )penOCD on the PC. IT can also be used to connect GBD via OpenOCD for debugging.

St-util

This is part of the st-link package and can be used to connect a GDB server to the Target

% ./st-util

st-util
2020-10-28T14:30:42 INFO common.c: F0xx: 8 KiB SRAM, 64 KiB flash in at least 1 KiB pages.
2020-10-28T14:30:42 INFO gdb-server.c: Listening at *:4242...

How To Unlock STM32F0x/STM32F1x Using OpenOCD

If you have received an error message indicating that the flash memory cannot be erased and that the device is blocked

> st-flash --reset write firmware.bin 0x8000000
st-flash 1.8.0
INFO common_flash.c: Attempting to write 24400 (0x5f50) bytes to stm32 address: 134217728 (0x8000000)
ERROR common_flash.c: Flash memory is write protected
WARN common_flash.c: Failed to erase_flash_page(0x8000000) == -1
ERROR common_flash.c: Failed to erase the flash prior to writing stlink_fwrite_flash() == -1

Attention for cloned chips!!!

• If you have a clone chip of the stm32, add the following near the top of stm32f1x.cfg (before the first If – statement):

  sudo nano /usr/share/openocd/scripts/target/stm32f1x.cfg

  set CPUTAPID 0

  and then proceed normally

You should proceed with the following command

> openocd -f interface/stlink-v2.cfg -f target/stm32f1x.cfg -c "init" -c "halt" -c "stm32f1x unlock 0" -c "reset halt" -c "exit"

After that, you need to physically remove power from the device in order for the reset to take effect.