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Register Structure & Connection
PnP BIOS. The assigned base address is located at offset 18h of
PCR. Therefore, users can read the PCR to know the base
address by using the BIOS function call. Note that the PCI-743X
registers are all 32 bits. The users can access these registers by
32 bits I/O instructions.
3.2 Registers Map
The PCI-7432 board requires 4 consecutive 8-bit addresses (32-
bit) in the PC I/O address space. The PCI-7433 and 7434
requires 8 consecutive addresses (32-bit) in the PC I/O address
space. Table 3.1 shows the I/O address of each register with
respect to the base address.
Address
Write
Read
PCI-7432
Base (0 - 3 )
Isolated DO
Isolated DI
PCI-7433
Base (0 - 7 )
--
Isolated DI
PCI-7434
Base (0 - 7 )
Isolated DO
--
Table 3.1. I/O Address Map of PCI-7432/33/34
DO
-- Digital Output
DI
-- Digital Input
Caution :
1.
I/O port is 32-bit width
2.
8-bit or 16-bit I/O access is not allowed.
3.2 Digital Input Register
There are 32 isolated digital input channels on PCI-7432 and 64
isolated digital input channels on the PCI-7433, each bit of based
address is corresponding to a signal on the digital input channel.
Address :
BASE + 0 ~ BASE + 3 for 7432
BASE + 0 ~ BASE + 7 for 7433
Attribute:
read only
Data Format :