This repo contains a port of Contiki for the TI MSP430 Launchpad. It is aimed at the msp430g2553 as the 'g2452 has some limitations (RAM, no hw UART etc) that requires extra care that is at best rudimentary now and likely won't happen soon.

Contiki serves an excellent middleground compared with the extremes of Arduino (Energia on LP) and doing everything yourself from the ground up. In my opinion, Arduino is too limited, especially when it comes to networking and complex applications.

-The most common way Arduino-users seem to get at networking is with an XBee, which in itself is very limited compared to Contiki/Rime. It limits you in terms of routing, topology, saving power etc.

-Complex applications are often implemented as huge state-machines which rapidly gets out of control. Contiki processes are lean, simple and powerful.

Doing it yourself from the ground up is a lesson in self-inflicted pain. Of course, you learn a lot by doing it, and it is the way I started out myself, but I think there is a lot of people that stopped playing with and enjoying stuff like the LP just because it is too hard. Still, after several years, I find doing the low-level stuff hard. Not to comprehend anymore, but to implement. Have you accidently used ''__bic_SR(...)'' instead of ''__bic_SR_onexit(...)''? Or ''DIVS_2'' instead of ''DIVS__2''? The former will end up stuck in an ISR and the latter will set the wrong clock speed. This Contiki port takes away a lot of that pain, giving you an easy way to build stuff while being very open for you to get down and dirty with the nitty-gritty details should you like to.

I recommend using Instant Contiki, which is an Ubuntu virtual machine with mspgcc and other tools installed from start.

• download and install eg Virtualbox, VMWare Player or similar software for virtual machines. They are free for personal use.
• download and run the Instant Contiki VM. see www.contiki-os.org for download links to the latest version.
• in the virtual machine, open a terminal and clone this repository ''git clone git://github.com/MarcusLunden/contiki-launchpad.git contiki-launchpad''
• check that your compiler path is ok by going into eg contiki-launchpad/examples/launchpad/blink and running ''msp430-gcc --version'' Then try compiling it with ''make all'' and uploading it to the Launchpad with ''make ul'' (I don't remember if mspdebug is included in the VM, otherwise you may need to download it first and make sure it is in the path)
• Check the examples in contiki/examples/launchpad Follow the README in that folder and experiment. Learn and get a feel for how to use processes, timers etc, working your way through and experimenting with processes.

If you choose not to pursue this path you can still compile and upload it in Linux, Windows, or OSX, as long as you have a working compiler and some utility to upload it to the device with. I use mspgcc and mspdebug, both free and open source. You could theoretically compile with IAR or Keil or whatever, but I haven't massaged the makefiles for this.

The msp430g2553 is very capable for being such a small and inexpensive device but is first and foremost limited in peripherals and RAM. For example, it has only two timers and not much RAM and thus I had to cut down on a lot of Contiki features and simplify others to make it fit. Other limitations are some Contiki features that I haven't ported yet.

• energest - energy estimation (save RAM)
• uIPv6 - some parts may come later, depends on how small packetbuf+Rime gets (save RAM).
• the sensors module was way too complex and hard to add new sensors so it is now replaced by a generic ADC module
• the rimestats module - it needs 72 B RAM = too much. see ''contiki/core/net/rime/rimestats.h''.
• packetbuf/Rime. I will remove quite many packetbuf attributes as they take a lot of RAM and are allocated even if they are used or not. This means that some Rime communication primitives do not work out of the box as they depend on eg the attribute for 'reliable' (ACK and retransmissions) so if you need those they will have to be re-implemented on top of this leaner Rime. (planned but not done yet...)

• radio drivers for the cheap yet powerful CC2500 transceiver. You can buy these as radio modules on ebay or aliexpress for approx 2$ each.
• SimpleRDC, a power-saving, low-power listening, radio duty cycling protocol. Stems from among others ContikiMAC, but with reduced complexity and RAM/ROM-requirements. Tweakable, defaults to 3% idle duty cycling with on avgerage 65ms latency. With the CC2500, this equates to an average power consumption of about 2 mW for the radio.
• node-id is burnt into Infomem with the script in tools/launchpad/burnid which uses mspdebug
• adc - instead of the sensors API, there is now a generic ADC API with functions for synchronous and asynch conversions etc. Pick your flavor.
• button - simple yet powerful button API
• PWM API for doing simple pulse width modulation, for eg dimming LEDs, with a straight-forward API and flexible regarding pins, period and duty cycle. There are two APIs due to limited timers: the 'simple-pwm' uses the same hw-timer as the clock so even the 2452 has one, but the 'pwm' needs a separate hw-timer but gives two pwm-channels
• Servo motor API
• lots and lots of shrinking of buffers etc.
• a driver for alphanumeric displays (a la Sparkfun)

Of course, this is subject to change and this file might not be up-to-date, and some of these points are likely more of the wishful thinking-character.

• a driver for HD44780-based LCD displays
• really simple (eg likely not that reliable or high performance) network stuff like leaf nodes to sink data routing, data dissemination through polite gossip and similar things.
• UART with interrupts; now it is just blocking which works but as the speed is limited in hardware to 9600 baud any printf's can block the mcu quite long time
• Contiki serial shell; now serial input works (wait for serial_input_events) but you have to parse the input yourself. I'll see how much space this takes, might have to skip it.
• simple unicast UDP
• would be cool with some simple service discovery stuff, or growl notifications! (growl could work nice, it's mostly static strings anyway that easily fit in ROM)
• having radio and serial output at the same time. Now, even with 100 bytes RAM left at compiletime, we still haven't got enough so applications crash.

• uIP; takes too much space
• nothing but a bare minimum of routing/neighbor tables; takes way too much space
• very generic SPI/I2C APIs as they are too application specific to be worthwhile

The biggest problem wasn't ROM space (program and const variables), it's RAM. By the way Contiki works, you use static variables a lot. This has the benefit that an application becomes more easy to analyze as you know more about it at compile time but the RAM requirements become harder. There is little hope of doing any serious routing on these for example.

The protothread abstraction basically folds out (preprocessor macro expansion) into function calls with a big switch-case for each process; any YIELD or WAIT_EVENT exits the function, hence any automatic (ie non-static or larger scope) variables are not saved across the block. So you use static a lot, and so they are stored in RAM. So I did simplify some things, removed others and managed to quite easily squeeze it into the 16kB/512B of the 2553 without any radio or Rime. With Rime, it's harder. The packet buffer, and queue buffer, needs a lot of space. I shrunk the packetbuf and removed any queuebufs.

The 2452, compared with the 2553, has one timer less, no hardware UART and only 256 byte RAM. This makes it much messier to use the 2452 with a Contiki that can printf as the timer would be needed for software UART but is now used for clock and rtimer. And just 256B RAM is quite narrow... But if you disable serial in the platform/launchpad/contiki-conf.h you can still fit Contiki on it to do simple things like buttons and LEDs and the like.

The 2231 and 2331 (?) where shipped with the early versions of Launchpad but are even more restrained than the 2452 so I won't spread the love to them.