reducing heat

[Chourizo]

I am trying to reduce the power usage and heat for a specific applications. I am only using one of the ethernet ports, and no wifi. Also, I am trying to reduce the CPU clock so it only does what I need.

In this forum there is information about how to do it:
mmio 0x1000003c 0x03040201

Is the mems command (included in the firmware) and mmio the same? It doesn't seem to be working.

I also tried this blog entry:
http://vonger.cn/?p=1880

Turning off all the unused ethernet ports. I don't really see any decrease in current.

I am exploring a couple more possibilities and maybe somebody has already tried it:

1. Using a lower input voltage than 5V. Would that reduce heat?
2. Using ffmpeg instead of mjpeg_streamer. ffmpeg might be lighter considering the lack of a web server.

[Vonger]

That register is for old vocore version with RT5350 core, can not use for vocore2.
in firmware we have a command named mem inside.

[Chourizo]

Thanks for the answer. Has anyone figured way the way to lower down the power consumption in the vocore2? (turning off unused ports, or lowering down the clock)

[Vonger]

Actually in datasheet, system control part, there are many register, you can try to turn off them one by one by mem command (or devmem)

[Chourizo]

I did some tests about this. The PHYs of the unused ethernet ports are actually disabled by default, so I am not sure if there is anything else that we can save there.

I haven't found a way to lower down the clock.

[Chourizo]

Going back to this.

I have like many different vocores v2 that I am using with cameras and leds. I wrote a program that will control the intensity of the leds based on the temperature of a board where the vocore is mounted.

I found that when the temperature reaches 55 degrees, some boards lose ethernet connection. Some boards will lose ethernet connection at lower temperatures, like 51-52 degrees.

The best scenario would be to reduce the heat on the vocore itself, but I haven't found a way to do this. The second best scenario would be identifying what's causing the connection drop in ethernet at such low temperatures.

Any help / commetn would be appreciated.

[Vonger]

call wifi off to reduce a lot of power usage. Or directly disable wifi in /etc/config/wireless.
Without wifi, power consume is less than 0.5watt. With wifi around 0.7~0.8watt.