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Picture of FCDEV3B board

We are proud to introduce our first FreeCalypso hardware product: a GSM mobile station development board. Our board features the same legendary TI Calypso GSM MS chipset that was used in commercial GSM/GPRS modems such as Openmoko's (our design is based on TI's Leonardo schematics and Openmoko's PCB layout), and functions as a standalone (or bare) GSM modem. The name of our board is FCDEV3B, which stands for FreeCalypso development board, triband.

We originally designed this board for our internal needs, to provide a proper platform for further development of our FreeCalypso software and firmware, but the product is a versatile GSM MS development board that can be used for all kinds of GSM learning and experimentation. The complete design files for our board are published, the Calypso chipset itself is also very well-documented, and ours is not the only software/firmware project that runs on the Calypso.

Hardware features


Compared to the mainstream commercial GSM modem kits for hobbyists and tinkerers and IoT/M2M applications and whatnot, our FreeCalypso GSM modem is unique in that it is explicitly designed to allow you to tinker with the inner workings of its firmware: you are explicitly encouraged to recompile our firmware from source and to flash your own fw builds into the modem, as well as to study our source, learn how it works, and make your own improvements which we never dreamt of. And if you totally dislike our firmware and wish to write your own completely from scratch instead, all hardware registers and functions are fully documented.

Compared to the ultra-cheap Motorola C1xx phones which are also based on the same Calypso chipset and which may thus seem no worse at first glance, our board is a fairly direct (by way of Openmoko) derivative of TI's Leonardo reference design, whereas Motorola's (really Compal's) hw design is considerably mutilated relative to the Leonardo baseline. Here are the serious shortcomings of Mot C1xx hardware:

Current status

In 2017 we have produced the first batch of FCDEV3B V1 PCB panels, and we have produced a total of 13 non-defective boards from those. Most of these boards have been either sold or given away to project supporters, leaving only a few boards in non-sellable condition for Mother's own use, hence these V1 boards are officially sold out. We do have two unpopulated PCB panels left, from which we could produce another 8 V1 boards, but it does not seem to make sense to build any more V1 boards given that they have a known hardware bug: sleep modes don't work because the way we have wired the flash reset line (following TI's reference schematics) has turned out to not be correct for the high-capacity flash chip we are using.

We now have a revised version of our board design that has this defect corrected (FCDEV3B V2), but we need money to make a new PCB fabrication and assembly run from the updated design files: we need about $5000 USD. Anyone who may be in a position to help, please email Mother Mychaela.