User`s manual

CYDAS UDR Library User’s Guide Analog Input Boards - CYDAS 16 and 4CYDAS 16 Series
59
Counter I/O
Counter functions and methods supported
UDR:
cbC8254Config(), cbCIn(), cbCLoad()
UDR for .NET: C8254Config(), CIn(), CLoad()
Counter argument values
CounterNum 1 to 3
The CYDAS 1802M1HR also supports these argument values:
4 to 6
Config HIGHONLASTCOUNT, ONESHOT, RATEGENERATOR, SQUAREWAVE, SOFTWARESTROBE,
HARDWARESTROBE
LoadValue
0 to 65535 (Refer to "16-bit values using a signed integer data type" on page 7 for
information on 16-bit values using unsigned integers.)
RegNum: LOADREG1, LOADREG2, LOADREG3
For CYDAS 1802M1HR the following argument values are also valid
LOADREG4, LOADREG5, LOADREG6
Triggering (CYDAS 1802M1HR only)
Trigger functions and methods supported
UDR:
cbSetTrigger()
UDR for .NET: SetTrigger()
Trigger argument values
TrigType TRIGPOSEDGE, TRIGNEGEDGE, GATEHIGH, GATELOW
Threshold
0 to 65535 (Refer to "16-bit values using a signed integer data type" on page 7 for
information on 16-bit values using unsigned integers.)
Hardware considerations
Pacing analog input
 Hardware pacing, external or internal clock supported.
 The packet size is 512 samples
 The
DMAIO option cannot be used while using the chan/gain queue on the CYDAS 1802STI board.
CYDAS 1802M1
If you use the timed analog functions with the CYDAS 1802M1 board to acquire more than 2048 data points,
you may not be able to achieve the full 1 MHz rate. On slow machines, these functions may hang if the scan
rate is fast, generally in the range of 500 to 700 kHz.
Determine the maximum rate by passing in different high rates until the maximum rate is achieved without
hanging the system. If the full 1.0 MHz rate is required, add a MEGA FIFO memory board and specify the
EXTMEMORY option on the call to cbAInScan()or AInScan().
CYDAS 1802M1HR also supports counter numbers 4 through 6, with counter 4 being the only independent
user counter.