Fan Control Device with Hardware Monitoring and Acoustic Noise Reduction Features
Datasheet
7.2.23
Register 6F: XOR Test Register
Register
Address
Read/
Bit 7
Bit 0
Default
Value
Register Name
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Write
(MSb)
(LSb)
6Fh
R/W
XOR Test Register
RES
RES
RES
RES
RES
RES
RES
XEN
00h
This register becomes read only when the Lock bit is set. Any further attempts to write to this register
shall have no effect.
The part incorporates an XOR tree test mode. When the test mode is enabled by setting the ‘XEN’ bit
high via SMBus, the part enters XOR test mode.
The following signals are included in the XOR test tree:
■
■
■
VID0, VID1, VID2, VID3, VID4
TACH1, TACH2, TACH3, TACH4
PWM2, PWM3
Since the test mode is XOR tree, the order of the signals in the tree is not important. SDA and SCL
are not included in the test tree.
7.2.24
Register 79h: SMSC Test Register
Register
Address
Read
Bit 7
Bit 0
Default
Value
Register Name
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
/Write
(MSb)
(LSb)
79h
R/W
SMSC Test Register
TST7
TST6
TST5
TST4 TST3 TST2
TST1
TST0
00h
This is a read/write register. Writing this register may produce unwanted results.
This register becomes read only when the Lock bit is set. Any further attempts to write to this register
shall have no effect.
7.2.25
Register 7Ah: SMSC Test Register
Register
Address
Read/
Write
Bit 7
Bit 0
Default
Value
Register Name
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
(MSb)
(LSb)
7Ah
R
SMSC Test Register
RES
TST6
TST5
TST4
TST3
TST2
TST1
TST0
00h
This is a read/write register. Writing this register may produce unwanted results.
7.2.26
Register 7Bh: SMSC Test Register
Register
Address
Read/
Write
Bit 7
Bit 0
Default
Value
Register Name
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
(MSb)
(LSb)
7Bh
R/W
SMSC Test Register
TST7
TST6
TST5
TST4
TST3
TST2
TST1
TST0
00h
This is a read/write register. Writing this register may produce unwanted results.
These registers become read only when the Lock bit is set. Any further attempts to write to these
registers shall have no effect.
SMSC EMC6D102
Revision 0.4 (04-05-05)
DATA6S7HEET
SMSC [ SMSC CORPORATION ]
