Multiple-Port Handshaking; Multiple-Port Input/Output - Keysight VXI Bus 75000 C Series User And Programming Manual

Using the Keysight E1458A Digital I/O Module
For example, the following BASIC program code will obtain a decimal value of
the state of the 32 data lines contained in ports 4, 5, 6, and 7.

Multiple-Port Handshaking

The SCPI command syntax to establish a multiple-port handshake and set
handshake timing is:
The optional keyword [:type], parameter DATAn, handshake <mode>, and
handshake delay <time> are all described earlier in this chapter. See the sections
"Handshake Modes", "Handshake Timing", and the introduction to "Multiple-Port
Operations" for explanations of these keywords and parameters.
Multiple-port handshaking has the following two anomalies regarding the CTL
and FLG control lines:
Input or Output handshaking using the CTL line. The CTL line is set TRUE or FALSE
sequentially on all ports involved in the operation, from the lowest-numbered
port to the highest-numbered port. A slight time delay exists between each port
setting the CTL line TRUE or FALSE. When using handshaking on multiple-port
operations, use the highest-numbered port CTL line to ensure correct data
transfer.
Input or Output handshaking using the FLG line. A change in the state of any FLG line
on any combined port continues the handshake operation for all the combined
ports. FLG lines can also be electrically combined through a switch setting (see
Chapter 2).

Multiple-Port Input/Output

Data input is performed using commands in the SCPI
MEASure:DIGigital:DATAn[:type] subsystem. Data output is performed using the
commands in SCPI [SOURce:]DIGital:DATAn[:type] subsystem.
46
Operation Values of n
:BYTE 0, 1, 2, 3, 4, 5, 6 ,7, 8, 9, 10 , or 11
:WORD 0, 2, 4, 6, 8, or 10
:LWORd 0, 4, or 8
:LW64 0
:LW96 0
120 OUTPUT @Dio;"MEAS:DIG:DATA4:LWORD?"
130 ENTER @Dio;Result
140 DISP "32 bit longword at port 4 "&Result
[SOURce:]DIGital:DATAn[:type]:HANDshake[:MODE] <mode>
[SOURce:]DIGital:DATAn[:type]:HANDshake:DELay <time>
Keysight E1458A 96-Channel Digital I/O Module User Guide
Multiple-Port Operations