National Instruments 321645c-01 用户手册
Chapter 2
Function Reference — DIG_Grp_Mode
NI-DAQ FRM for PC Compatibles
2-166
©
National Instruments Corporation
DIG_Grp_Mode
Format
status = DIG_Grp_Mode (deviceNumber, group, protocol, edge, reqPol, ackPol, delayTime)
Purpose
Configures the specified group for handshake signal modes.
Parameters
Input
Parameter Discussion
group is the group to be configured.
Range:
1 or 2.
protocol indicates the basic handshaking mode. Refer to your device user manual for details
on using the protocol parameter.
Range is 0 through 2 for the DIO-32F, or 0 through 4 for the DIO 6533 (DIO-32HS).
on using the protocol parameter.
Range is 0 through 2 for the DIO-32F, or 0 through 4 for the DIO 6533 (DIO-32HS).
0:
Group is configured for held-ACK (level-ACK)
handshake protocol.
1:
Group is configured for pulsed-ACK handshake protocol.
2:
Group is configured for
pulsed-ACK handshake protocol with variable ACK
pulse width.
3:
Group is configured for synchronous burst handshaking, using the REQ, ACK,
and PCLK signals.
and PCLK signals.
4:
Group is configured to emulate 8255 (DIO-24) handshake timing.
Note
This function does not support variable-length ACK pulse width (signal = 2) on
AT-DIO-32F Revision B and earlier.
AT-DIO-32F Revision B and earlier.
Name
Type
Description
deviceNumber
i16
assigned by configuration utility
group
i16
group
protocol
i16
basic handshaking system
edge
i16
rising-edge or falling-edge pulsed signals
reqPol
i16
request signal is to be active high or active low
ackPol
i16
acknowledge handshake signal is to be active high
or active low
or active low
delayTime
i16
data settling time allowed