Environmental Monitoring and Control Device
Datasheet
7.2 LIMIT AND CONFIGURATION REGISTERS.............................................................................................29
7.3 DEVICE SET-UP ...............................................................................................................................30
7.4 PWM FAN SPEED CONTROL.............................................................................................................30
7.4.1 Manual Fan Control Operating Mode......................................................................................30
7.4.2 Auto Fan Control Operating Mode ..........................................................................................31
7.4.3 Spin Up....................................................................................................................................34
7.4.4 Hottest Option..........................................................................................................................35
7.5.1FANFSaPnEETDacMhOoNmITeOteRrINInGp..u..t.s........................................................................................................................................................................................................................3355
7.5
7.5.2 Detection of a Stalled Fan .......................................................................................................36
7.5.3 Fan Interrupt Status Bits..........................................................................................................36
7.6 LINKING FAN TACHOMETERS TO PWMS ............................................................................................36
7.7 SYSTEM SYNCHRONIZATION..............................................................................................................36
CHAPTER 8
REGISTER SET................................................................................................................37
8.1 UNDEFINED REGISTERS....................................................................................................................40
8.2 REGISTER 10H: SMSC TEST REGISTER ............................................................................................40
8.3 REGISTER 1E, 1FH: OFFSET REGISTERS...........................................................................................40
8.4 REGISTERS 20-24H, 70-72H: VOLTAGE READING ..............................................................................40
8.5 REGISTERS 25-27H: TEMPERATURE READING ...................................................................................41
8.6 REGISTERS 28-2FH: FAN TACHOMETER READING..............................................................................42
8.7
8.7.1REGMISTaEnRuSal3M0-o3d2eH.:..C...U..R..R..E..N..T..P...W...M....D...U..T..Y...............................................................................................................................................................................4432
8.8 REGISTER 3EH: COMPANY ID ...........................................................................................................44
8.9 REGISTER 3FH: VERSION / STEPPING................................................................................................44
8.10
8.11
8.12
8.13
8.14
8.15
8.16
8.17
8.18
REGISTER 40H: READY/LOCK/START MONITORING ........................................................................44
REGISTER 41H: INTERRUPT STATUS REGISTER 1............................................................................46
REGISTER 42H: INTERRUPT STATUS REGISTER 2............................................................................47
REGISTER 7DH: INTERRUPT STATUS REGISTER 3...........................................................................48
REGISTER 43H: VID......................................................................................................................48
REGISTERS 44-4DH, 73-78H: VOLTAGE LIMIT REGISTERS ..............................................................49
REGISTERS 4E-53H: TEMPERATURE LIMIT REGISTERS ...................................................................50
REGISTERS 54-5BH: FAN TACHOMETER LOW LIMIT ........................................................................51
8.18.1REGBISiTtsER[7S:55]CZ-o5nEeH/:MFoAdNeC..O..N..F..I.G..U..R..A..T..I.O..N..........................................................................................................................................................................5511
8.18.2
8.18.3
8.18.4
Bit [4] PWM Invert ................................................................................................................52
Bit [3] Reserved....................................................................................................................52
Bits [2:0] Spin Up..................................................................................................................52
REGISTERS 5F-61H: AUTO FAN SPEED RANGE, PWM FREQUENCY ................................................53
REGISTER 62H, 63H: MIN/OFF, SPIKE SMOOTHING.........................................................................55
REGISTERS 64-66H: MINIMUM PWM DUTY CYCLE .........................................................................56
REGISTERS 67-69H: TEMPERATURE LIMIT ....................................................................................57
REGISTERS 6A-6CH: ABSOLUTE TEMPERATURE LIMIT ....................................................................57
REGISTERS 6D-6EH: ZONE HYSTERESIS REGISTERS..................................................................58
REGISTER 6F: XOR TEST REGISTER .............................................................................................59
REGISTER 79H: TEST MODE REGISTER..........................................................................................59
REGISTER 7AH: ERROR DEBUG REGISTER.....................................................................................60
REGISTER 7BH: TEST DIGITAL VALUE REGISTER ............................................................................61
REGISTER 7CH: SPECIAL FUNCTION REGISTER ..............................................................................61
REGISTER 7EH: INTERRUPT ENABLE REGISTER..............................................................................62
REGISTER 7FH: CONFIGURATION REGISTER...................................................................................63
REGISTER 80H: FAN TEMP INTERRUPT ENABLE REGISTER ..............................................................64
REGISTER 81H: TACH_PWM REGISTER .......................................................................................65
8.19
8.20
8.21
8.22
8.23
8.24
8.25
8.26
8.27
8.28
8.29
8.30
8.31
8.32
8.33
8.34
8.34.1REGBISiTtE[4R]8O3NH:..S..Y..N..C...P...U..L.S..E...C...O..N..F..I.G..U..R..A..T..I.O..N...R..E...G...I.S..T..E...R..:..O...N../.O...F..F...........................................................................................6666
8.35
REGISTERS 86-88H: SMOOTH TEMPERATURE READING REGISTERS................................................66
SMSC EMC6D100/EMC6D101
Page 5
Rev. 09-09-04
DATASHEET
SMSC [ SMSC CORPORATION ]
