Fix spelling error.

Fix instructions of how to use stm32flash.

Author: DarinelSanguino

guides/flashing.md

@@ -16,16 +16,7 @@ Each template contains a make file located at the root of the template and is ca
 
 ### Flashing tool
 
-There are differennt interfaces (serial, I2C, SPI, SWD, etc.) and programs you can use to flash code to your device. Make sure to set the `FLASHING_TOOL` variable in your makefile to the name of your flashing tool. Currently the project has two options available:
-
- - [st-flash](https://github.com/stlink-org/stlink) uses SWD interface. (default)
- - [stm32flash](https://github.com/stm32duino/stm32flash) uses serial interface.
- 
-### Serial port
-
-Follow this step only if you are using `stm32flash`.
-
-In your makefile set `FLASHING_SERIAL_PORT` variable to the name of the serial port to which your device is connected.
+There are different interfaces (serial, I2C, SPI, SWD, etc.) and programs you can use to flash code to your device. If you want to use [stm32flash](https://github.com/stm32duino/stm32flash), in your makefile set the variables`FLASHING_TOOL` to 'stm32flash' and `FLASHING_SERIAL_PORT` to the name of the serial port to which your device is connected.
 
 ### Connect an LED
 
@@ -54,8 +45,7 @@ Most development boards come with jumpers or (DIP-)switches to set the BOOT-mode
 Before flashing your device, make sure to have done all the things on this checklist:
 
  - Make sure to change the `DEVICE` variable value in the make file to the name of your device;
- - Make sure to set the `FLASHING_TOOL` variable to the name of your flashing tool;
- - If you are using `stm32flash`, make sure to set the `FLASHING_SERIAL_PORT` variable to the name of your serial port;
+ - If you are using `stm32flash`, make sure to set the `FLASHING_TOOL` variable to that name and `FLASHING_SERIAL_PORT` to the name of your serial port;
  - Make sure to have changed the pin to "blink" if the LED on your development board is not connected to pin `PC13`;
  - Optionally, make sure to connect an LED to your development board if your development board does not have one built-in;
  - Make sure that you have properly connected the debugger to your development board;