Force Computers PENT/CPCI-721, Installation Manual

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Maps and Registers PENT/CPCI-720/2/3 Registers
PENT/CPCI-721 6 - 7
I
2
C Register
The I
2
C register is used for data transfer settings on the I
2
C bus and pro-
vides access to the program-readable vintage registers for the base
board, the I/O board, the lower and upper memory modules, the VGA-
IO720 as well as the registers controlling the configuration of the tem-
perature sensors.
Table 16: I
2
C Register
Address: 0108
16
Bit Value Description Access Settings
0 DIR Direction bit for I
2
C data r/w =0
Data is written to
the data line.
=1 (default)
Data is read from
the data line.
1 CLK Clock line of the I
2
C bus r/w =0
Clock line is low.
=1 (default)
Clock line is
high.
2 DATA_IN Stores the current value of
the data line. r =0
Data line is low.
=1
Data line is high.
3 Reserved Reserved 5 Undefined