Hi all.
I want to share finished firmware that allows to use some fans like TFC1212DE-SP07 and alike which have inverted PWM regulation. In general this firmware is simular to ckolivas 20130703, but also with my changes in cgminer included. Some options redefining constants added (see github readme). Also, as a little bonus, i included this patch, that shows % of HW errors.

https://github.com/re-invader/avalon-fw

My changes to cgminer also present here if you want to build it from sources

https://github.com/re-invader/cgminer

Next goal is to improove temperature regulation algorithm, as powerful fans seems to produce temperature  oscillations that is hardly converged ( temp up -> fan up -> temp down -> fan down -> temp up ) in some cases, especially on large min/max range.

If you find it useful you can say "thanks" by mining on default pool settings.
Feel free to ask any questions.

Thanks for your help and answer, cgminer is written in C and compiled by gcc
In general i have some ideas that i'll try to implement later, but it's not a quick fix. Im thinking on a simple and effective solution. For now i just increased a little avg temperature collection / fan regulation interval ( by option --avalon-fanwait ) and it seems working.

Do you use your avalon with the  TFC1212DE-SP07 to get it cooler or to have the same temp but maybe more quiet ?

I've installed 3 TFC1212DE, flashed your 20130714 firmware and set the --avalon-invert-pwm option. But for some reason the fans do not seem to speed up when the temp is getting up. The fan RPM stays stable at around 2580 RPM, and my temp2 and temp3 sensors are 60C.

Do you have any ideas why my fans don't run any harder when the temp is getting up? According to specs fans are 5500 rpm. When I only connect +12V and ground fans spins at 4800RPM, so they can spin harder dan this 2580 rpm.

Also option  --avalon-fan 100 does not seem to work.

Without this option the fans starts at around 2500 rpm, and it slowly drops to 0 rpm, so looks like inverted pwm to me


Thank you, will give it a try and let you know!

I indeed took power straight from the PSU (I'm still using the standard Enermax GX850 PSU). Pulling ~700watt at the wall, so plenty of room for the 2 fans.

This options:
--avalon-invert-pwm --avalon-fan 30-90 --avalon-fanwait 5 --avalon-fanfactor 160
--avalon-invert-pwm --avalon-fan 99-100 --avalon-fanfactor 160
--avalon-invert-pwm --avalon-fan 9-10 --avalon-fanfactor 160
--avalon-fan 99-100 --avalon-fanfactor 160
--avalon-fan 9-10 --avalon-fanfactor 160

Give me those readings:

Status   MHS5s   MinerCount   AsicCount   Frequency   Fan1   Fan2   Fan3   Temp1   Temp2   Temp3   NMW   Firmware
                                    
Alive   79276.71   24   10   350   0   2720   2720   34   52   54   10   20130714
Alive   85793.17   24   10   350   0   2560   2560   35   56   57   4   20130714
Alive   73036.38   24   10   350   0   0   0   36   56   58   2   20130714
Alive   64177.27   24   10   350   0   0   0   36   57   59   0   20130714
Alive   1823.91   24   10   350   0   1920   1920   36   57   59   0   20130714

Extended the fan cable, because the original was only 5cm. I even redid it and use thicker cable:



Can this somehow cause incorrect readings on the sense- or control-wire?

If your fan have the same ground with avalon controller via PSU and wires connected properly, as far as i can tell from this picture, everything is fine.

I don't get it, why with the option --avalon-invert-pwm you have 2560 rpm @ 100% fan, and with 90% fan = 2720 rpm ..
Thats a really strange issue, fan is looking exactly the same like mine ( Can you also make a picture of it's label from other side just for reference? )

I can guess you have a batch 2 unit, and maybe there is some difference in avalon controller fpga code related to fan pwm ..
( I still not received mine so i can't tell now for sure. )

To figure out what is really happening, can you make more tests with altering --avalon-fan option by 10% steps and post rpm sensor result?
( Try to find values where you have max fanspeed. )

--avalon-invert-pwm --avalon-fan 100 --avalon-fanfactor 160
--avalon-invert-pwm --avalon-fan 90 --avalon-fanfactor 160
...
--avalon-invert-pwm --avalon-fan 20 --avalon-fanfactor 160
...
( Also try the same without --avalon-invert-pwm option )

I checked, and it's exactly the same! Only difference is the code near triangle - mine is "7807a24R", "7808A24R". Looks like it's a serial number.


Ok. Then we'll see if it can be fixed via software. You can also try to plug it somewhere else like in motherboard and play with PWM value to see if you can really control them, to exclude the possibility of difference in avalon controller.

ADD:

Im starting to think that it could be a controller related issue.
I have controller v1.52 , and i can't stop the fans (for example) with option --avalon-fan 0.
Which effectively mean, that in inverted pwm mode you can't reach max fanspeed.
Seems like controller can't pass low pwm values redefining it to some min_pwm constant, or have some internal regulation depending on sensor reading temperature ( i noticed that once fan rpm value was less than 2000 , but i can't set it now less than 2400, which is very strange )
It just my thoughts based on observation of b2 unit behavior, i would try to install fans later and see if i got the same issue as yours.

ADD:

I have found a "workaround". Seems that controller is indeed going into some "helper" mode to control the fans if the temp2 sensor is present. So i unplugged it, and seems that now i can control the fans like i want.

So, in short, the solution is to unplug temp2 sensor! (closest to unit intake side)

ADD:

I tested new fans with temp2 sensor unplugged, it seems to be working as in b1 unit.

If it helps, I got the 4400 RPM model from that company and I have had no issues and they all run great with the avalon OC firmware.