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Cpu speed and Fan control

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acapon
Junior(0)
Cpu speed and Fan control

Hi Guys,
I have just got an ultra96.
 
I thought the main cores were 1.5ghz but they seem to be set to 1.2ghz in cpu_info_max_frequency. Is there a reson for this?
 
Also there doesn't seem to be any fan control, the fan spinning flat out is driving me mad.
Even loading the 4 cores up 100% each my max temp is only 52 so I'm thinking this fan is running a bit fast.
 
Is there any way to enable fan control?
 
Many thanks for any help
 
Andy
 
 
 

fletch
Moderator(23)
The Ultra96 has a -1 speed

The Ultra96 has a -1 speed grade device, which has a max APU frequency of 1.2 GHz. See DS925, Table 28.

The fan can be controlled via GPIO F4. However, we have not implemented an example for this yet. The idea is to read the temperature and adjust the pulse width on F4. Perhaps someone in the community has already done this and will share.

Bryan

acapon
Junior(0)
Hi Bryan,

Hi Bryan,
 
Thanks very much for the prompt reply.
Shame about the speed rating, I was mistaken.
 
Thanks for the pointer on GPIO F4, I will take a look...
 
Many thanks
 
Andy

acapon
Junior(0)
Hi Again,

Hi Again,
With the default boot is it possible to get this GPIO into userspace via /sys/class/gpio ?
 
Thanks
 
Andy
 

fletch
Moderator(23)
Unfortunately, no. However,

Unfortunately, no. However, it should not be that hard to add. I will request that this get added to the next BSP that gets released.

Bryan

acapon
Junior(0)
Thanks Bryan.

Thanks Bryan.
I was going to look into this aday to see if I can get it going, I will let you know how it goes...