[Oberon] RiskFive: New Hardware for Oberon / RISC5 ?

Skulski, Wojciech skulski at pas.rochester.edu
Tue Jul 24 14:54:13 CEST 2018


Concerning the new hardware, I reworked RiskFive after realizing that the DDR3 memory is bringing significant problems to the system design, such as latencies and caching. So I decided to develop a new version of that board with ZBT RAM. I released the information two days ago on the website RiskFive.com. Today I received the quote for building the "bone" board. This night I finished the motherboard files to be sent for the quote. We will build these boards.

Mind it, RiskFive will be an expensive board. It is meant to be a development platform from which a future board/boards will emerge. For example, there are two 100M Ethernet channels on the motherboard. Obviously, for a practical application you need only one. I am providing two Ethernet chips for the development of two application tiers. Then there is the USB-3 channel for something really fast like data streaming. An interesting spin is that you can map the entire board memory on the USB-3 interface and dump it to the PC. 

A significant goal is the 24 bit color. I provided a professional video DAC rather trying to simulate it with a bunch of el cheapo resistors. The ZBT architecture will allow to develop a very efficient and very simple video channel with 8-bit pixel mapped to 24-bit color via a lookup table (a "palette").

Concerning System Verilog, professor Pong Chu just published his Verilog version of his SOC design book. I received the copy three days ago. It looks magnificent. Highly recommended! Professor Chu is using Artix-7, the exact same chip which I am using on RiskFive. The entire firmware framework is now available from Professor Pong website, both in VHDL and in System Verilog. We do not need to scrounge around for firmware bits and pieces, because a high quality FPro framework is now available. 

My intent is open hardware. The motherboard design files will be released as soon as I actually order this board. The FOM design files will be available in PDF to everyone, and in full source on request. 

Thank you,

More information about the Oberon mailing list