Updated the readme for UART service

Author: Kevin Townsend

nRF51822/projects/uartservice/README.md

@@ -1,21 +1,34 @@
-Project Name
+UART Service
 ============
 
-About this project
+This project shows how custom services and characteristics can be defined and manipulated on the nRF51822.
+
+A sample 'UART' type service with two characteristics as follows:
+
+- The first characteristic acts as a **TXD** line, with **indicate** enabled, which allows us to know definitively if the transmitted data was received or not.
+
+- The second characteristic acts as the **RXD** line and has **write** enabled so that the connected GATT client device (the phone/tablet/etc.) can send data back to the GATT server (the nRF51822).
+
+Target SDK/SD
+=============
+
+- **SDK**: v5.1.0
+- **SoftDevice**: v6.0.0
 
 Building this Project
 =====================
 
 To build a clean copy of your project in release mode, enter the same folder as your Makefile on the command-line and enter the following command:
 
-- make clean release
+```
+  make clean release
+```
 
 Other relevant make targets are:
 
-- make
-- make debug
-- make flash-softdevice (flashes Softdevice via JLink)
-- make flash (flashes output hex file via JLink)
-- make erase-all (erases flash)
-- make startdebug - (starts GDBServer & GDB via JLink)
-- make stopdebug - (stops GDBServer)
+- `make` is an alias for `make debug` below
+- `make debug` builds a .hex file that includes debug data (larger, unoptimized binaries useful to debug via GDB Server)
+- `make release` builds an optimized release version of the firmware
+- `make clean` removes and previous build artifacts
+- `make flash` flashes the nRF51 via JLink and nrfjprog.exe (currently Windows only)
+