Stanford Research Systems RGA100, Operating Manual And Programming Reference

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Ionizer Control Commands 6-33
SRS Residual Gas Analyzer
If a filament check fails at any time the following steps are taken automatically:
filament is turned off, Degas_LED is turned off, jump to step 12).
8. At the end of the time specified by the parameter (and if no problems were
encountered) the Degas_LED is turned off.
9. Ionizer goes back to pre-Degas configuration
10. The electron emission current is reprogrammed to its pre-Degas value and
background filament protection is reenabled.
11. The Filament LED is updated.
12. The STATUS byte is sent out to the host computer to indicate the DEGAS
process is over.
Any command recieved before degassing is over will stop the process
immediately without the STATUS byte being echoed to the computer. During
degassing a check for new commands is done once a second, so a time margin
must be allowed once the stop command is issued for the Degas command to
react to it. Some more time (a few seconds) must be provided to let the pre-degas
electron emission current be reestablished at the end.
Parameters:
DG0: Do nothing command. Commonly used to stop degassing. Nothing is
echoed over RS232.
DGparam, param: 0-20 : The parameter represents the degas time in minutes.
The first minute is used to ramp the current up to 20 mA.
DG*: The default time is used to degas.
Default=3 (minutes)
Error Checking:
Number parameters must be within the accepted range, and must be integers.
No parameter (i. e. DG) is treated as a parameter error.
No queries are allowed.
EEparam, param: 25 - 105, *, ?
Description : Electron Energy (eV).
Echo: STATUS error byte or query response.
Set the Electron Impact Ionization Energy of the ionizer. The parameter
represents the desired electron ionization energy in units of eV.
If the filament is emitting electrons at the time the command is invoked, the
repeller voltage is immediately reconfigured to provide the desired electron
energy, while the ion energy and electron emission currents remain unafected. If