Code Sourcery g++ Lite and Programmer's Notepad for LPC1768 development

Eclipse is a fantastic IDE but some may prefer the light weight Programmer's Notepad. This post will show you how easy development for LPC1768 on a Windows box using CodeSourcery g++ Lite and Programmers notepad is.

1. Install CodeSourcery g++ Lite for ARM. Dowload the latest EABI target from CodeSourcery website.

2. Install Programmers Notepad. You can get the latest version here.

3. Open Programmers Notepad.

4. Goto Tools -> Options. Select tools in the left pane.

6. Now, click on Add. First, we'll add the Build Tool. Enter "Build" in the name field. Search where you have installed CodeSourcery and look for "cs-make.exe" as the command. Typically, cs-make is found in a place like this "C:\Program Files\CodeSourcery\Sourcery G++ Lite\bin\cs-make.exe" . In the folder field, enter "%d" and select a shortcut familiar to you. In the Save field, select "Save all files". Click on OK.

7. Repeat the procedure for Clean. Click on Add again. Enter "Clean" as the name. Select cs-make as the command again. Enter "clean" as the parameter. The other fields are entered as in the previous step. After entering everything, it should look like this.

Hit OK and OK the Options window too.

8. Now, you should have two tools, Build and Clean listed as shown below.

9. Start a new project. File -> New Project. Enter a suitable name and choose the folder where you want your work stored.

Hit OK.

10. Download the latest Quick Start Code from Cortex - m3 tutorials on google code. Extract it to your project location. As of date, this is the latest version. If you are using the USB secondary bootloader presented earlier in this blog, then use this one. The two Quick Start code bases are identical save for the fact that the one meant for the bootloader has a different flash start location. 8 KB of flash in the beginning is left aside for the bootloader and then the application code follows. The slight modification is the linker file LPC17xx.ld

11. Right Click on the project name in Programmers notepad and add the files you just extracted.

12. Hit F5 (or whatever short cut you use or Click on Tools -> Build) to compile and generate the .bin and Hex file.

You should get a message in the output window which shows successful compilation. The output message should be similar to this :
> "C:\Program Files\CodeSourcery\Sourcery G++ Lite\bin\cs-make.exe"
arm-none-eabi-gcc -W -Wall -fno-common -O2 --std=gnu99 -fgnu89-inline -mcpu=cortex-m3 -mthumb -ffunction-sections -fdata-sections -g3 -c core_cm3.c -o core_cm3.o
arm-none-eabi-gcc -W -Wall -fno-common -O2 --std=gnu99 -fgnu89-inline -mcpu=cortex-m3 -mthumb -ffunction-sections -fdata-sections -g3 -c startup_LPC17xx.c -o startup_LPC17xx.o
arm-none-eabi-gcc -W -Wall -fno-common -O2 --std=gnu99 -fgnu89-inline -mcpu=cortex-m3 -mthumb -ffunction-sections -fdata-sections -g3 -c system_LPC17xx.c -o system_LPC17xx.o
arm-none-eabi-g++ -W -Wall -fno-common -mcpu=cortex-m3 -mthumb -O2 -c main.cpp -o main.o
arm-none-eabi-ld -Map=main.map -TLPC17xx.ld --gc-sections -nodefaultlibs -nostartfiles  core_cm3.o startup_LPC17xx.o system_LPC17xx.o  main.o -o main.elf
arm-none-eabi-size main.elf
   text       data        bss        dec        hex    filename
    808          0          0        808        328    main.elf
arm-none-eabi-objcopy -R .stack -O ihex main.elf main.hex
arm-none-eabi-objcopy -O binary -j .text -j .data main.elf main.bin

> Process Exit Code: 0
> Time Taken: 00:01

If you see the size of compiled file being declared, you know the build is successful. Otherwise, you'll see an error message indicating which file(s) has an error.

Voila ! Getting started with Cortex M3 is so very easy.

A few questions that might come up.

1. I want to start a new project. Should I write my own start up files, makefile etc.. ?

- No. The Quick Start Code Base is just for that. Each time you start a new project, add the files from the Quick Start Code Base and use that as a starting point.

2. My project has more source files like "uart.h" and "uart.c". Should I modify the makefile ?

- No. The makefile included in the Quick Start Code Base compiles every Source file the project directory. So, there is no need to touch the makefile at all for simple projects ! Just import the code base and you're off. Every assmbler source (*.S ), C Source (*.c ) and CPP source (*.cpp) in the project directory is assumed to be needed, compiled and presented to the linker. While this may not be the best method, this makes things easy to get started with. When the project gets too big, then it might be a good time to visit the makefile and organise the project properly.

UPDATE : The LPC17xx code base has been improved since the writing of this post. The newer code base links against libc, supports C++ and offers a minimal implementation of syscalls. Download the latest version here.