Re: hp clock does not talk to hp 71 Message #12 Posted by Sylvain Cote on 29 July 2012, 9:35 a.m., in response to message #9 by Hans Holzach
I just went through the manual and I now understand the behaviour of the device.
If I understood correctly the device will send it clock continuously on the loop when it becomes the talker (TAD) and stop when he received an untalk (UNT)
So the sequence should be ...
- configure device
- send untalk
- make device the talker
- read from the loop
- send untalk
- parse, extract and format data
- show/use the formatted data
Have you tried reading from the loop but with a limit on the number of bytes ?
In packed format the unit should send 9 bytes repeatedly.
Since we do not known when the snapshot will happen, we need to
dimention the input buffer 2 times the size of the data and then find the start record in the buffer.
Using the above procedure, at the "read from the loop" line
the following should do the trick
ENTER LOOP USING "18A";D$
Sylvain
PS: To have a better understanding of what happen on the loop I suggest that you buy the PIL-Box from JF Garnier and use the Virtual HP-IL softwares from Christoph Gießelink.
Those will allow you to have a sniffer on the loop and then see what is happening on it.
Edited: 29 July 2012, 9:48 a.m.
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