2.2 I/O Port Location
The OME-PIO-D56/OME-PIO-D24 consists of one 24-bit bi-directional port, one
16 bit input port and one 16 bit output port (only for OME-PIO-D56). The 24-bit port
supports three 8-bit groups: PA, PB & PC. Each 8-bit group can be individually
configured to function as either inputs or outputs. All groups using 24-bit bi-
directional ports are configured as inputs upon power-up or reset. The I/O port
locations are as follows:
Connector of
OME-PIO-D56/D24
PA0 ~ PA7
PB0 ~ PB7
PC0 ~ PC7
CON3
(DI/O)
Port0 Port1 Port2
Connector of OME-PIO-D56
Description
CON1 D/O
CON2 D/I
Refer to Sec. 2.1 for board layout & I/O port location.
Note: PC0, PC1, PC2 and PC3 can be used as interrupt signal source. Refer to Sec.
2.4 for more information.
2.3 Enabling I/O Operation
2.3.1 DI/DO Port Architecture (CON3)
Upon power-up, all D/I/O port (CON3) operations are disabled. The RESET\
signal controls the enable/disable state of D/I/O port. Refer to Sec. 3.3.1 for more
information about RESET\ signal. The power-up states are as follows:
•
All D/I/O operations are disabled
•
All three D/I/O ports are configured as D/I port
•
All D/O latch register are undefined.(refer to Sec. 2.3.2)
Initialization must be performed before using these D/I/Os. The recommended
steps are as follows:
Step 1: Find address-mapping of OME-PIO/PISO cards (refer to Sec. 3.1)
Step 2: Enable all D/I/O operations (refer to Sec. 3.3.1)
Step 3: Configure the three ports (in CON3) to their expected D/I/O state &
send the initial value to all D/O ports (refer to Sec. 3.3.8)
Refer to DEMO1.C for demo program.
OME-PIO-D56/OME-PIO-D24 User Manual (Ver.2.1, Oct/2003)
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