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OPC6 on BlackIce dev board

A project log for OPC-5 - a CPU for FPGA, in one page

A 16-bit CPU, with 16 registers, described in 66 lines of code - with HDL, emulators and a macro assembler.

Ed SEd S 08/24/2017 at 17:190 Comments

Another great leap forward: OPC5/6 has been seen running on several Xilinx chips: the Spartan 3 on an OHO GOP board, and the LX9 on a cheapo Starter Board and on an Avnet micro board. But now, we have it working on the BlackIce dev board: a nice little board with a Lattice FPGA, an ARM microcontroller, a USB-to-serial interface chip, and a fast 16bit wide SRAM. Look:

At first, we used only the on-chip RAM, but in the course of an afternoon and evening we got the CPU running at 40MHz with the external SRAM and talking to a host over a serial port. A little later, with the help of a firmware update, we were able to talk on serial over USB. (You'll notice two USB connectors: one is for the ARM and for downloading design data while the other is free for communication with the FPGA.)

As an extra bonus, there's a fully open source toolchain for this Lattice chip.

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