STM32_Programmer_CLI.exe -fchecksum c:\users\mwright\915rev4.hex
STM32_Programmer_CLI.exe -c port=SWD -vb 1 -e all -w c:\users\mwright\915rev4.hex 0x08000000 -v 
STM32_Programmer_CLI.exe -c port=SWD -checksum