Omega OME-PIO-D144 - Manual (Page 34)

3.3.9 I/O Selection Control Register
(Write): wBase+0xc8
Bit 7
Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0 0 CN2_PC CN2_PB CN2_PA CN1_PC CN1_PB CN1_PA
(Write): wBase+0xcc
Bit 7
Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0 0 CN4_PC CN4_PB CN4_PA CN3_PC CN3_PB CN3_PA
(Write): wBase+0xd0
Bit 7
Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
0 0 CN6_PC CN6_PB CN6_PA CN5_PC CN5_PB CN5_PA
Note. Refer to Sec. 3.1 for more information about wBase.
For example:
CN1_PA=1Æ Port is used as a D/I port.
CN1_PA=0Æ Port is used as a D/O port.
There are eighteen 8-bit I/O ports in the OME-PIO-D144. Every I/O port can be
programmed as D/I or D/O port. When the PC is first powered up, all eighteen ports
are used as D/I port. The I/O port location is given as follows:
Connector of OME-PIO-
D144
PA0 to PA7 PB0 to PB7 PC0 to PC7
CN1 CN1_PA CN1_PB CN1_PC
CN2 CN2_PA CN2_PB CN2_PC
CN3 CN3_PA CN3_PB CN3_PC
CN4 CN4_PA CN4_PB CN4_PC
CN5 CN5_PA CN5_PB CN5_PC
CN6 CN6_PA CN6_PB CN6_PC
outp(wBase+0xc8,0); /* CN1_PA/PB/PC to CN2_PA/PB/PC are all D/O port */
outp(wBase+0xcc,0x3f); /* CN3_PA/PB/PC to CN4_PA/PB/PC are all D/I port */
outp(wBase+0xd0,0x38); /* CN5_PA/PB/PC are all D/O port */
/* CN6_PA/PB/PC are all D/I port */
Refer to Sec. 2.2 for I/O Port Location.
OME-PIO-D144 User’s Manual (Ver.2.1, Sep/2001) ---- 32