updated gnss example readme

ST-B-L072Z-LRWAN1/longfi-us915-cayenne-gnss/README.md

@@ -1,24 +1,7 @@
-# ST B-L072Z-LRWAN1 - GNSS Example
+# ST B-L072Z-LRWAN1 - Cayenne GNSS Example
 
 This example demonstrates sending GNSS data in [CayenneLPP](https://developers.mydevices.com/cayenne/docs/lora/#lora-cayenne-low-power-payload) format, using a B-L072Z-LRWAN1 development board with a X-NUCLEO-GNSS1A1 expansion shield, to the myDevices Cayenne dashboard. For more information on adding your device to the Helium network, visit our quickstart guide [here](https://developer.helium.com/console/quickstart). For more information on adding your device to myDevices Cayenne, visit our guide [here](https://developer.helium.com/console/integrations/mydevices-cayenne-integration).
 
-## Required Arduino Libraries
-
-From the Arduino IDE, open the Library Manager (Sketch->Include Library->Manage Libraries). In the search box, type the library name below and install the latest version.
-
-[MCCI Arduino LoRaWAN Library](https://github.com/mcci-catena/arduino-lmic)  
-[CayenneLPP](https://github.com/ElectronicCats/CayenneLPP)  
-[X-NUCLEO-GNSS1A1](https://github.com/stm32duino/X-NUCLEO-GNSS1A1)  
-
-## Required Arduino Board Support
-
-### B-L072Z-LRWAN1 - ST STM32L0 Discovery kit  
-Install board support package, find instructions [here](https://github.com/stm32duino/Arduino_Core_STM32#getting-started).  
-
-Arduino IDE:  
-1. Select Tools -> Board: -> Discovery 
-2. Select Tools -> Board part number: -> Discovery L072Z-LRWAN1 
-
 ## Required Hardware
 
 ### B-L072Z-LRWAN1 - ST STM32L0 Discovery kit
@@ -30,11 +13,51 @@ Arduino IDE:
 
 [X-NUCLEO-GNSS1A1 Product Page](https://www.st.com/en/ecosystems/x-nucleo-gnss1a1.html)  
 [X-NUCLEO-GNSS1A1 User Manual](https://www.st.com/resource/en/user_manual/dm00453103-getting-started-with-the-xnucleognss1a1-expansion-board-based-on-teseoliv3f-tiny-gnss-module-for-stm32-nucleo-stmicroelectronics.pdf)  
-## Programming (Uploading Method):
 
-#### STM32CubeProgrammer(SWD)
+## Required Driver (Windows Only)
-Will use onboard ST-Link(Flasher/Debugger) to upload sketch.  
+Download driver [here](https://www.st.com/en/development-tools/stsw-link009.html).
-Download and Install required utility from ST [here](https://www.st.com/en/development-tools/stm32cubeprog.html).  
 
+## Required Arduino Libraries
+
+From the Arduino IDE, open the Library Manager (Sketch->Include Library->Manage Libraries). In the search box, type the library name below and install the latest version.
+
+[CayenneLPP](https://github.com/ElectronicCats/CayenneLPP)  
+[X-NUCLEO-GNSS1A1](https://github.com/stm32duino/X-NUCLEO-GNSS1A1)  
+
+## Required Board Support
+
+### Arduino Core for STM32L0 
 Arduino IDE:  
-Select Tools -> Upload Method -> STM32CubeProgrammer(SWD)
+1. Navigate to (File > Preferences)
+Find the section at the bottom called Additional Boards Manager URLs: 
+2. Add the URL below to the list and click ok to close the preferences.
+```
+https://grumpyoldpizza.github.io/ArduinoCore-stm32l0/package_stm32l0_boards_index.json
+```
+![arduino_preferences](https://i.gyazo.com/148c4bc3646aaf71f8d9a0499c82fec4.png)
+
+3. Open Boards Manager: Select Tools > Board: > Boards Manager...
+4. Search for "Tlera Corp STM32L0 Boards"
+5. Select the newest version and install.
+
+### Temporary Manual Fix
+This issue has been fixed but not released yet, until then you will need to insert three lines of code in a library file.
+Insert the following:
+```
+#ifndef NULL
+#define NULL  0
+#endif
+```
+Into the file found here:
+linux: /home/{user}/Arduino/libraries/IBM_LMIC_framework/src/lmic  
+windows: Documents/Arduino/libraries/IBM_LMIC_framework/src/lmic  
+mac os: Documents/Arduino/libraries/IBM_LMIC_framework/src/lmic  
+
+![arduino_board_support](https://i.gyazo.com/216457ad64b8f85016d1b6d7cc6df044.png)
+## Programming (Uploading):
+
+Arduino IDE:   
+1. Select Board: Tools > Board: > B-L072Z-LRWAN1  
+2. Select Port: Tools > Port > COM# or /dev/ttyACM#(B-L072Z-LRWAN1)
+3. Upload Sketch: Select > Upload
+4. (Optional) View Serial Debug Output: Tools > Serial Monitor > 9600 baud