SR400 photon counter Labview drivers

[m-s]

Hello,

I am designing an application that uses the SR400 two channel gated photon counter. I downloaded the plug and play drivers from IDN and I find that there are 4 basic VIs - A gate, B gate, Config and Read. I am planning on using the counter with T select set to the internal 10MHz clock and count A and B for a fixed amount of time (say 3 seconds) in a single count period (just avoiding complications that crop up with multiple count periods in my application). When I look at the VIs, I do not see a Labview equivalent for the start command (CS) or any way to preset T counter. Is this set of VIs feature complete, or do I have to enter GPIB commands through VISA somehow (how ?) ?

I have years of GPIB programming experience, but am very new with Labview (ver. 7.1 on Linux). My experience with the other Labview instrument libraries I am using indicates that IDN drivers are feature complete, but am beginning to have doubts regarding this particular driver.

Regarding the Config VI, does it start the count as soon as one selects Tselect to 10MHz ? The manual states quite clearly that this does not happen until a START command is received in some way :

"When the START key is pressed, a START
command is received from the computer interface,
or the EXTERNAL START input is pulsed,
counter T is enabled to count. The COUNT
PERIOD begins with the first pulse from T
counter's input after START. The COUNT
PERIOD enables counters A and B to count their
respective inputs. If the A GATE and B GATE are
CW or continuous, all pulses that occur during the
COUNT PERIOD are counted. If the gates are
enabled, only the pulses that occur during those
gates which fall within the COUNT PERIOD are
counted."

It continues :

"Counter T is presettable from 1 to 9E11. When
counter T reaches the preset count, the COUNT
PERIOD is terminated and counting is halted on
all counters. When the input to counter T is the 10
MHz crystal timebase, the COUNT PERIOD is a
fixed time interval from 100 ns to 25 hours. "

(I am just guessing that the folks at Stanford Research decided to capitalize some of the terms to reduce possible confusion.).

Hence my confusion above. Or does the Read VI start the count when it is called ? If so, how do I set how long I want the count to be ?

Thanks.

[TCPlomp]

Hello m-s,

I don't know this driver but:
since you know GPIB programming it should be easy to track this. Just double click on the read.vi and look for VISA-writes and see if the correct command is written.
Another feature is NI-spy this program can monitor anything that is written on the GPIB-bus.

Although LabVIEW is a graphical language the commands to the GPIB bus are just ascii (look for text surrounded by a pink/purple border) there is a lot of GPIB information on these boards: GPIB/VISA board

Ton