HiFive1-based ARGB controller

This is a project to drive ARGB-based computer case lighting from a HiFive1 board. I am using this with a Silverstone SST-RVZ03B-ARGB case, but it will likely work with others. I ditched the built-in 8051-based LED controller board and replaced it with the HiFive1 board, which I had collecting dust anyway.

Setup

This software drives a 16-LED (the number can be changed by changing N_LEDS in the source code) WS2812B (Neopixel-ish) LED strip using the SPI controller on a HiFive1 evaluation board. The SoC on this board is a SiFive Freedom E310.

SDK

First you need to install the Freedom-E-SDK as described here. You need the v1_0 branch, not Metal (master branch). This is an intentional choice because I prefer the low-level register abstractions. Build it from source or install pre-built binaries.

Next edit config.mk and set the SDKDIR variable to where you installed the SDK.

Hardware

This uses the old HiFive1 board, not the HiFive1 Rev B. Some changes to the code, as well as a level-shifter, may be necessary to make it work on that.

Set the I/O voltage jumper on the HiFive1 board to 5V. It will likely not work at all at 3.3V because the signal voltage will be too low to register.

Headers

There seem to be two types of ARGB headers:

5V RGB header three(of four)-wire "addressable RGB" (ARGB) light strip

    |     |     |     |     |
    | +5V |  D  | N/A | GND |
    |     |     |     |     |

Three-pin connector "Mizucool Gigabyte VDG header", also just "VDG header":

         -       -
    -------------------
    |     |     |     |
    | +5V | D   | GND |
    |     |     |     |
    -------------------
    |-    -     -    -|
    -------------------

In either case, connect the D wire of the LED strip to PIN-3 (SPI1_MOSI) on the HiFive1, the +5V to a power supply, and the GND to the same ground as the HiFive1.

Compile the code

Just type make software to compile the code.

Upload and run the code

Connect your HiFive1 to the host computer in the usual way and type make upload. That should upload the code.

UART protocol

A simple protocol is used at 115200 baud. First, a single-character effect identifier is sent from the host, the device replies with C, then the host sends optional parameters. After the parameters are received the effect starts the next frame. See handle_uart_interrupt().

Available effects

x Reset to initial color (no parameters)
o Turn all leds off (no parameters)
f Manual color setting (follow with 3 * N_LEDS bytes for R, G, B for each led)
s Simplex noise (a kind of lava lamp effect).
- First byte is mode-
  - 0 FULLRGB: full RGB noise
  - 1 COLOR1: interpolate between black and one color
  - 2 COLOR2: interpolate between black and two colors (using two noise channels)
  - 3 COLORN: interpolate between black and white, multiplied with a color per led
- Then N_LEDS times 3 bytes for RGB color parameters. These always need to be provided even for the modes that use no, or only one, color.
r Rainbow (no parameters at this time)
p Pulse all leds (no parameters at this time)
2 One or two moving dots (no parameters at this time)

Credits

Loosely based on hifive1-neopixel by Curt Brune, but it uses SPI instead of GPIO bit-banging, takes commands through the UART, and uses interrupts to drive timing. Also, the effects have been changed. Not much of the original code remains. But thanks a lot for getting me started.

vmedea / hifive1-argb-fx