ADLINK Technology NuDAQ, User Manual

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Register Format 37
COS Setup/Latch Registers
The PCI-7442 provides a Change of State (COS) interrupt function
on any one of digital input channel. This function allows you to
monitor the status of digital input channels by setting these regis-
ters.
By enabling the COS Setup registers, it will generate an interrupt
when the corresponding channel changes its state.
When COS occurs, the COS latch registers also latch the
IDI[31..0], IDI[63..32] data, respectively. Once you clear the inter-
rupt request, the COS latch register automatically clears. Since
you can simply read these registers to know the statuses after
interrupts, these registers free the CPU from the overwhelming
task of constantly polling all inputs, enabling it to handle other
tasks.
Address R/W Value Mapping (MSB----LSB)
BASE+0x08h W IDI_COS_EN[15…0]
BASE+0x0Ah W IDI_COS_EN[31...16]
BASE+0x48h W IDI_COS_EN[47...32]
BASE+0x4Ah W IDI_COS_EN[63...48]
IDI_COS_EN [n]: Change-of-State function enable of IDI
channel n, n = 0 – 63
Bit value: 0: Disable COS function
1: Enable COS function
Address R/W Value Mapping (MSB----LSB)
BASE+0x08h R IDI_COS_LATCH_DATA[15…0]
BASE+0x0Ah R IDI_COS_LATCH_DATA[31...16]
BASE+0x48h R IDI_COS_LATCH_DATA[47...32]
BASE+0x4Ah R IDI_COS_LATCH_DATA[63...48]
Bit value: 1: The input is on.
0: The input is off (initial value).