Lake Shore 625, User Manual

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Lake Shore Model 625 Superconducting MPS User’s Manual
Computer Interface Operation 5-23
5.1.5.5 Program Operation
Once either example program is running, try the following commands and observe the response of the instrument. Input
from the user is shown in
bold and terminators are added by the program. The word [term] indicates the required
terminators included with the response.
ENTER COMMAND? *IDN?
Identification query. Instrument will return a string identifying itself.
RESPONSE: LSCI,MODEL625,1234567,06122003[term]
ENTER COMMAND? RDGR? 1
Ohm reading query. Instrument will return a string with the present
resistance reading from channel 1.
RESPONSE: +273.150E+00[term]
ENTER COMMAND? HTRRNG 0
Heater range command. Instrument will turn off the heater. No
response will be sent.
ENTER COMMAND? HTRRNG?
Heater range query. Instrument will return a string with the present
heater range setting.
RESPONSE: 0[term]
ENTER COMMAND? HTRRNG 1;HTRRNG?
Heater range command followed by a query. Instrument will change to
heater Low setting then return a string
RESPONSE: 1[term]
with the present setting.
The following are additional notes on using either IEEE-488 Interface program.
•
If you enter a correctly spelled query without a “
?
,” nothing will be returned. Incorrectly spelled commands and
queries are ignored. Commands and queries should have a space separating the command and associated parameters.
•
Leading zeros and zeros following a decimal point are not needed in a command string, but are sent in response to a
query. A leading “+” is not required but a leading “–”
is required.
5.1.6 Troubleshooting
New Installation
1. Check instrument address.
2. Always send terminators.
3. Send entire message string at one time including terminators.
4. Send only one simple command at a time until communication is established.
5. Be sure to spell commands correctly and use proper syntax.
6.
Attempt both ‘Talk’ and ‘Listen’ functions. If one works but not the other, the hardware connection is working, so
look at syntax, terminators, and command format.
7.
If only one message is received after resetting the interface, check the “repeat addressing” setting. It should be
enabled.
Old Installation No Longer Working
8. Power instrument off then on again to see if it is a soft failure.
9. Power computer off then on again to see if the IEEE card is locked up.
10. Verify that the address has not been changed on the instrument during a memory reset.
11. Check all cable connections.
Intermittent Lockups
12. Check cable connections and length.
13. Increase delay between all commands to 50 ms to make sure instrument is not being over loaded.