Synthesizing a Bitcoin Miner for the OR1200Tom Tracy IIECE 6502 – ASIC/SOCSpring 2014

How bitcoin works, by Joshua J. Romero, Brandon Palacio & Karlssonwilker Inc.

Miners are paid 50 Bitcoins (~$22k) to the miner that finds the nonce that generates the ‘winning’ blockThey are also paid a small transaction fee

MotivationIncrease the Bitcoin mining capabilities of the OR1200.

Make more money.

http://blockchain.info/charts/difficulty

GoalIntegrate the Bitcoin miner into the class’s OR1200 processor.

1. Synthesize the Wishbone interface for the OR12002. Synthesize the Bitcoin Miner (accelerator)3. Synthesize the Slave Wishbone interface for the Bitcoin Miner

Procedure1. Modify the Johnson_Counter DC example scripts for the new RTL.2. Attempt DC

Fail? Continue to 1Success? Wonderful; continue to 3

3. Modify the Johnson_Counter ICC example scripts for the new RTL.4. Attempt ICC

Fail? Continue to 3Success? Wonderful!

Handle DRC Errors

Synthesizing the OR1200 Wishbone

Interface

Wishbone Interface Results

Ports and Lessons Learned

Lessons

1. Use zroute instead of global route_optTodo: Solve 234 spacing and area DRC errors.

Synthesizing the Bitcoin Miner

Bitcoin Miner Results

Ports and Lessons Learned

Lessons

ovDigest contains the last 8 digests, and is used for simulation only. Turn this off; significantly reduces size.Synopsys is not perfect:

74 hours to run one command

Wishbone Slave Interface

The plan was to use wbgen2 to generate the Verilog for the Wishbone bus. It requires a configuration file, and then generates the RTL to be synthesized

Getting an error: Unknown register style.

http://www.ohwr.org/projects/wishbone-gen/wiki/Wbgen2_Documentation

Future Work1. Solve OR1200 WB interface and Bitcoin Miner DRC errors.2. Solve the error and finish the Wishbone slave interface.3. Complete memory block