LM(4)

NAME
lm - National Semiconductor LM78, LM79 and compatible hardware monitors

SYNOPSIS
lm0 at isa? port 0x280 flags 0x00
lm1 at isa? port 0x290 flags 0x00
lm2 at isa? port 0x310 flags 0x00
lm3 at isa? port 0xa00 flags 0x00
lm0 at pnpbios0 index ? flags 0x00
lm0 at iic? addr 0x2e flags 0x00
lm* at wbsio?

DESCRIPTION
The lm driver provides support for the National Semiconductor LM series hardware monitors and register compatible chips to be used with the envsys(4) API.

The original LM78 hardware monitor supports 11 sensors:
Sensor | Units | Typical Use
IN0 | uV DC | Core voltage
IN1 | uV DC | unknown
IN2 | uV DC | +3.3V
IN3 | uV DC | +5V
IN4 | uV DC | +12V
IN5 | uV DC | -12V
IN6 | uV DC | -5V
Temp | uK | Motherboard Temperature
Fan0 | RPM | Fan
Fan1 | RPM | Chassis Fan
Fan2 | RPM | Fan
For other devices, sensors' names and numbers will be different.

Due to hardware limitations, fresh sensor data is only available every 2 seconds.

HARDWARE
Chips supported by the lm driver include:

National Semiconductor LM78, LM78-J, LM79, and LM81.

Nuvoton NCT5104D, NCT6775F, NCT6776F, NCT6102D, NCT6104D, NCT6106D, NCT6779D, NCT6791D, NCT6792D, NCT6793D, NCT6795D, and NCT6796D.

Winbond W83627HF*, W83627THF*, W83627EHF*, W83627DHG*, W83637HF*, W83697HF*, W83781D, W83782D*, W83783S*, W83791D*, W83791SD, and W83792D.

ASUS AS99127F.

For most of the Winbond chips (identified with a * above), the flags configuration option can be specified to select the type of temperature sensor:
flags | Sensor Type
0 | Thermistor diode (Power-On default)
1 | Pentium-II diode
2 | 2N3904 Bipolar
4 | Thermistor diode

SEE ALSO
envsys(4), wbsio(4), envstat(8)

HISTORY
The lm device appeared in NetBSD 1.5.

CAVEATS
Some vendors connect these chips to non-standard thermal diodes and resistors. This will result in bogus sensor values.

BUGS
Interrupt support is unimplemented.

There are currently no known pnpbios IDs assigned to LM chips.