PCI 730 & PC104P-30 User Manual
Eagle Technology - Data Acquisition
Counter Timer
The counter sub-system is supported by functions to Write, Configure and controlling the
gate. There are 3 counters and 1 frequency generator. See the table below that shows the
relation of the counters and their assigned numbers.
Writing the initial counter value
A single call is necessary to write a counter’s initial load value.
Counter
Description
Resolution
CT0 Counter
0
16-bits
CT1 Counter
1
16-bits
CT2 Counter
2
16-bits
CT3 Frequency
Scaler
16-bits
Table 4-1 Counter Resolution
Calculating Frequency Scaler’s output frequency
Frequency = 20MHz / (2 * (Value + 1))
API-CALL
Long EDRE_CTWrite(ulng Sn, ulng Ct, ulng Value)
The serial number, counter-number, and a value must be passed by the calling function. A
return code will indicate if any errors occurred.
ACTIVEX CALL
Long EDRECTX.Write(long Port, ulng Value)
The port number and value to be written needs to be passed and the returned value holds an
error or the value read. If the value is negative an error did occur.
Reading the counter value
A single call is necessary to read a counter.
API-CALL
Long EDRE_CTRead(ulng Sn, ulng Ct, pulng Value)
The serial number, counter-number, and a reference parameter must be passed by the calling
function. A return code will indicate if any errors occurred.
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