Stanford Research Systems RGA100, Operating Manual And Programming Reference

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6-64 Tuning Commands
SRS Residual Gas Analyzer
where m is the mass in amu, and DAC8(m) is the 8 bit setting at that mass.
The purpose of the Peak Width Tuning Procedure is to determine the values of DI
and DS so that all the peaks in an analog spectrum have the desired peak width
(typically 1 amu).
The DI command is used to program the value of the DI peak tuning parameter during the
Peak Width Tuning Procedure. The value is saved in the non-volatile memory of the
RGA Head and used by the firmware to generate DAC8(m) during measurements.
Note to Supervisors : A calibration disable jumper (JP100) available on the circuit board
can be used by a supervisor to block any attempt to modify the value of the DI parameter.
Supervisors may use this feature to prevent accidental changes in the calibration
parameters by inexperienced operators. Setting JP100 will disable peak tuning of the
Head.
Parameters:
DIparam, param: 0 - 255:
If Calibration is enabled by the jumper JP100 (See CE
Command) the value of DI in non-volatile memory is updated and the internal scan
parameters used to program the DC during scans and single mass measurements are
updated accordingly.
DI* : Use this format to replace the peak tuning parameter with the original factory setting
for DI. The factory value is retrieved from memory, and used as the new parameter value
to excecute the command as above
DI? : Query. Returns over RS232 the value of DI currently stored in memory.
Error checking:
The absence of a parameter (i. e. DI) is treated as an error in the parameter.
This parameter is protected by an internal jumper (JP100) and a Protection-Violation
error will result if the jumper is in the Calibration Disable mode (See CE command).
DSparam, param: -0.8500 - +0.8500, *, ?
Description : DS Parameter adjust (Peak Width Tuning command).
JP100 Jumper protected.
Echo: Query Response.
Important:
RGA200 DS range: -1.2750 - +1.2750
RGA100 DS range: -2.5500 - +2.5500
Program the value of DS during the Peak Width Tuning Procedure. The parameter (one
of four peak tuning parameters) represents the DS value, in units of bits/amu.
Warning: Please read the Peak Tuning Section of the RGA Tuning Chapter before using
this command.