diff --git a/tools/win/serial_upload.bat b/tools/win/serial_upload.bat
index c59a646..d733be7 100644
--- a/tools/win/serial_upload.bat
+++ b/tools/win/serial_upload.bat
@@ -1,23 +1,23 @@
 @echo off
-rem
-rem parameters are: 
-
-rem Note: %~dp0 get path of this batch file, so path parameter is no longer required
-
+rem: Note %~dp0 get path of this batch file
+rem: Need to change drive if My Documents is on a drive other than C:
+set driverLetter=%~dp0
+set driverLetter=%driverLetter:~0,2%
+%driverLetter%
 cd %~dp0
 rem: the two line below are needed to fix path issues with incorrect slashes before the bin file name
 set str=%4
 set str=%str:/=\%
 stm32flash -g 0x8000000 -b 230400 -w %str% %1 
-rem C:\Python27\python.exe stm32loader.py -e -w -p %1 -g -b 115200  %str%
+rem: C:\Python27\python.exe stm32loader.py -e -w -p %1 -g -b 115200  %str%
 
-rem ------------- use STM's own uploader 
-rem ---- Need to remove the COM bit from the comm port as the STM prog just wants the number
+rem: ------------- use STM's own uploader 
+rem: ---- Need to remove the COM bit from the comm port as the STM prog just wants the number
 set commport=%1
 set commportnum=%commport:COM=%
-rem --- The maple board may nee the -i setting to be -i STM32_Med-density_128K or STM32_Med-density_64K
-rem ---- 64 bit version
-rem "%ProgramFiles(x86)%\STMicroelectronics\Software\Flash Loader Demonstrator\STMFlashLoader.exe"  -c --pn %commportnum% --br 230400  -i STM32_High-density_256K -e --all -d --fn %str% --a 0x8000000 -r --a 0x8000000 
+rem: --- The maple board may nee the -i setting to be -i STM32_Med-density_128K or STM32_Med-density_64K
+rem: ---- 64 bit version
+rem: "%ProgramFiles(x86)%\STMicroelectronics\Software\Flash Loader Demonstrator\STMFlashLoader.exe"  -c --pn %commportnum% --br 230400  -i STM32_High-density_256K -e --all -d --fn %str% --a 0x8000000 -r --a 0x8000000 
 
-rem  -- 32 bit version
-rem "%ProgramFiles%\STMicroelectronics\Software\Flash Loader Demonstrator\STMFlashLoader.exe"  -c --pn %commportnum% --br 230400  -i STM32_Med-density_64K -e --all -d --fn %str% --a 0x8000000 -r --a 0x8000000 
+rem:  -- 32 bit version
+rem: "%ProgramFiles%\STMicroelectronics\Software\Flash Loader Demonstrator\STMFlashLoader.exe"  -c --pn %commportnum% --br 230400  -i STM32_Med-density_64K -e --all -d --fn %str% --a 0x8000000 -r --a 0x8000000