2 data port b control register (base + 1), 3 data port c control register (base + 2) – Omega Engineering IOP-241 User Manual
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5.2
Data Port B Control Register (Base + 1)
The Data Port B Control Register contains the control bits for I/O channels DATA8 - DATA15.
Each I/O channel may be individually programmed for input by writing a '1' to the
appropriate bit of this register.
General Purpose I/O bit 8
DATA8
0
General Purpose I/O bit 9
DATA9
1
General Purpose I/O bit 10
DATA10
2
General Purpose I/O bit 11
DATA11
3
General Purpose I/O bit 12
DATA12
4
General Purpose I/O bit 13
DATA13
5
General Purpose I/O bit 14
DATA14
6
General Purpose I/O bit 15
DATA15
7
Description
Name
Bit
Table 5-3. Data Port B Control Register
5.3
Data Port C Control Register (Base + 2)
The Data Port C Control Register contains the control bits for I/O channels DATA16 -
DATA23. Each I/O channel may be individually programmed for input by writing a '1' to the
appropriate bit of this register. In addition, any of these eight I/O channels which are
programmed for input may also be used to generate interrupts. In order to program an I/O
channel as an interrupt source, the Port C Interrupt Enable Register must be set appropriately.
The I/O channel must also be programmed for input by writing a '1' to the appropriate bit of
the Data Port C Control Register.
General Purpose I/O bit 16 and Interrupt Line 0
DATA16/INT0
0
General Purpose I/O bit 17 and Interrupt Line 1
DATA17/INT1
1
General Purpose I/O bit 18 and Interrupt Line 2
DATA18/INT2
2
General Purpose I/O bit 19 and Interrupt Line 3
DATA19/INT3
3
General Purpose I/O bit 20 and Interrupt Line 4
DATA20/INT4
4
General Purpose I/O bit 21 and Interrupt Line 5
DATA21/INT5
5
General Purpose I/O bit 22 and Interrupt Line 6
DATA22/INT6
6
General Purpose I/O bit 23 and Interrupt Line 7
DATA23/INT7
7
Description
Name
Bit
Table 5-4. Data Port C Control Register
IOP-241 Users Manual 26