acer_5750G_fan_maximiser icon indicating copy to clipboard operation
acer_5750G_fan_maximiser copied to clipboard

Investigate on what other models does this might work

Open neduard opened this issue 8 years ago • 7 comments

It would be really good to compile a list of devices on which this whole direct-port-writing-to-control-fan business works on or MIGHT work.

Currently users have reported working on a few other models apart from the original Acer 5750G (see README).

A few pointers if anybody is interested in working on this (@LeonardKoenig? @dehein?)

  1. Start from the existing models which others have confirmed and look for schematics. We're basically looking for matching chipsets.
    1. One way would be search for schematics (for example "Acer 5750G schematics pdf" in Google yelds this) and take note of the components.
    2. The relevant components IMO are the EC and the PCH: For example, the schematic above shows the EC is a KB930 which is connected to the Intel Cougar Point PCH via an LPC bus.
  2. Find out what are the common features of the laptops that this works (hopefully it will be the EC or PCH)

neduard avatar Jul 22 '16 09:07 neduard

IIRC I once read something about this being related to the InsydeH2O BIOS/firmware, so this could be a point too. Maybe looking at those BIOS-modder forums.

ljrk0 avatar Jul 22 '16 09:07 ljrk0

I agree, this would be an excellent opportunity for somebody looking to learn a bit more about hardware and what is in the machines we're using :)

neduard avatar Jul 22 '16 09:07 neduard

Definitely. I will see how much I can contribute but I'm not at home the next weeks, so my possibilities are limited.

The PDF you linked looks promising and even has a page dedicated to fan control :)

ljrk0 avatar Jul 22 '16 10:07 ljrk0

Couldn't find a schematics for KB930 yet (though you seem to be right (acer forums), but for kb9012 which seems to be a successor (schematics) as it says

Compared with ENE KB930, KB9012 is added with AWFCS application for PECI 3.0 implement for latest Intel feature.

in the PDF. The observations about fixed/automatic fan speed seem to be confirmed there too:

The fan controller can be configured to control PWM known as FANPWM. FANPWM could operate as automatic-FAN mode or Fixed-FAN mode.

Especially p. 128 (PDF-Page: 138) seems to be interesting: "LPC I/O 0x68/0x6C Configuration"

It really seems to fit into the picture, as now much of the code makes more sense:

  • Writing to port 0x6c is for sending commands (control the fan)
  • Writing to port 0x68 is for sending data (parameters: MAX/NORMAL)
  • Checking for inb(0x68) & 0x80 == 0 is checking whether I/O interface is busy
  • Checking for inb(0x68) & 0x02 == 0 is checking whether the Input Buffer Flag is unset (waiting for input)
  • Writing 0xff clears the I/O busy flag
  • The values 0x59, 0x77, 0x76 are specific to the controller -- I've not found any documentation on that (yet). These are the actual commands/parameters that control the fan.

ljrk0 avatar Aug 10 '16 18:08 ljrk0

I just want to say that this method also works well on my notebook - Acer Aspire E5-572G with Intel Lynx Point PCH and ENE KB9012QF EC (connected to PCH via an LPC bus).

Schematic

mx2345 avatar Nov 07 '16 21:11 mx2345

Also confirmed to work on Acer Aspire V3-551-8479 (Q5Wx8 with VA50_CM motherboard). Allows me to finally be able to control the fan.

fordcars avatar Mar 29 '20 18:03 fordcars

I have found a schematics for KB930. There are some informations about fan control in this document. KB3930.pdf

godvino avatar Sep 18 '20 16:09 godvino