System Workbench for STM32

I adding information from console in debug mode before error appears:

Open On-Chip Debugger 0.10.0-dev-00004-gcef2a8c-dirty (2017-08-31-14:07)
Licensed under GNU GPL v2
For bug reports, read
http://openocd.org/doc/doxygen/bugs.html
srst_only separate srst_nogate srst_open_drain connect_assert_srst
Info : The selected transport took over low-level target control. The results might differ compared to plain JTAG/SWD
adapter speed: 950 kHz
adapter_nsrst_delay: 100
Info : tcl server disabled
Info : telnet server disabled
Info : clock speed 950 kHz
Info : STLINK v2 JTAG v29 API v2 M v18 VID 0x0483 PID 0x374B
Info : using stlink api v2
Info : Target voltage: 3.271287
Info : Stlink adapter speed set to 950 kHz
Info : STM32F091RCTx.cpu: hardware has 4 breakpoints, 2 watchpoints
Info : accepting 'gdb' connection on tcp/3333
Info : Stlink adapter speed set to 950 kHz
adapter speed: 950 kHz
STM32F091RCTx.cpu: target state: halted
target halted due to debug-request, current mode: Thread
xPSR: 0xc1000000 pc: 0x080021e8 msp: 0x20008000
Info : Stlink adapter speed set to 950 kHz
adapter speed: 950 kHz
Info : device id = 0x10006442
Info : flash size = 256kbytes
Info : Stlink adapter speed set to 950 kHz
adapter speed: 950 kHz
STM32F091RCTx.cpu: target state: halted
target halted due to debug-request, current mode: Thread
xPSR: 0xc1000000 pc: 0x080021e8 msp: 0x20008000
Info : dropped 'gdb' connection