FPGA development has advanced dramatically in the last year, and this is entirely due to an open-source toolchain for Lattice’s iCE40 FPGA. Last spring, the bitstream for this FPGA was reverse engineered and a toolchain made available for anything that can run Linux, including a Raspberry Pi. [Dave] from Xess thought it was high time for a Raspberry Pi FPGA board. With the help of this open-source toolchain, he can program this FPGA board right on the Raspberry Pi.
The inspiration for [Dave]’s board came from the XuLA and StickIt! boards that give the Raspberry Pi an FPGA hat. These boards had a problem; the Xilinx bitstreams had to be compiled on a ‘real’ PC and brought over to the Raspberry Pi world. The new project – the CAT Board – brings an entire FPGA dev kit over to the Raspberry Pi.
The hardware for the CAT Board is a Lattice iCE-HX8K, 32 MBytes of SDRAM, a serial configuration flash, LEDs, buttons, DIP switches, grove connectors, and SATA connectors (although [Dave] is just using these for differential signals; he doesn’t know if he can get SATA hard drives to work with this board).
Despite some problems with his board house, [Dave] eventually got his FPGA working, or at least the bitstream configuration part, and he can blink a pair of LEDs with a Raspberry Pi and programmable logic. The Hello World for this project is done, and now the only limit is how many gates are on this FPGA.



ons of C++ were compiled with CFront, a compiler that generated C code which was then compiled as normal. Around the 1990s, it’s unclear when, numerous native compilers became available, notably for PCs, which lead to explosive growth from 400,000 users to an estimated 4.4 million today.
Behind the clock is an Arduino driving a MAX7219 LED controller. Using the MAX7219 was a challenge because it expects a grid of LEDs while the clock needs a linear array. [Dylan] used a line of individual LEDs wired to match what the controller wanted. A rotary encoder tells the processor the position of the arm so the Arduino sketch can determine which LEDs should be lit to show the time and clock face.
Most spy movies (at least the ones worth their salt) will include a few scenes that depict nerds in a van listening in on conversations remotely and causing the victims phones to do things like turn themselves or their cameras on. We have been made to believe that it takes an entire van of equipment and one or two MIT level hackers to pull this off. Turns out all it takes is about $2300, some know how, and an unsuspecting target with a set of microphone-equipped headphones attached to their phone.
