Changeset 5355

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Timestamp:
10/04/08 13:32:03 (6 years ago)
Author:
khali
Message:

Add PWM experiment information from ticket #2350.

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1 modified

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  • lm-sensors/trunk/doc/chips/w83781d

    r4139 r5355  
    733733# PWM 
    734734 
    735 Additional info about PWM on the AS99127F (may apply to other Asus 
     735* Additional info about PWM on the AS99127F (may apply to other Asus 
    736736chips as well) by Jean Delvare as of 2004-04-09: 
    737737 
     
    776776AS99127F chips at all. 
    777777 
    778 Additional info about PWM on the AS99127F rev.1 by Hector Martin: 
     778* Additional info about PWM on the AS99127F rev.1 by Hector Martin: 
    779779 
    780780I've been fiddling around with the (in)famous 0x59 register and 
     
    798798with speedfan under Windows, where 0-15% would be off, 15-2x% (can't 
    799799remember the exact value) would be 70% and higher would be full on. 
     800 
     801* Additional info about PWM on the AS99127F rev.1 from lm-sensors 
     802  ticket #2350: 
     803 
     804I conducted some experiment on Asus P3B-F motherboard with AS99127F 
     805(Ver. 1). 
     806 
     807I confirm that 0x59 register control the CPU_Fan Header on this 
     808motherboard, and 0x5a register control PWR_Fan. 
     809 
     810In order to reduce the dependency of specific fan, the measurement is 
     811conducted with a digital scope without fan connected. I found out that 
     812P3B-F actually output variable DC voltage on fan header center pin, 
     813looks like PWM is filtered on this motherboard. 
     814 
     815Here are some of measurements: 
     816 
     8170x80     20 mV 
     8180x81     20 mV 
     8190x82    232 mV 
     8200x83   1.2  V 
     8210x84   2.31 V 
     8220x85   3.44 V 
     8230x86   4.62 V 
     8240x87   5.81 V 
     8250x88   7.01 V 
     8269x89   8.22 V 
     8270x8a   9.42 V 
     8280x8b  10.6  V 
     8290x8c  11.9  V 
     8300x8d  12.4  V 
     8310x8e  12.4  V 
     8320x8f  12.4  V 
     833