Stanford Research Systems RGA100, Operating Manual And Programming Reference

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Scan and Measurement Commands 6-47
SRS Residual Gas Analyzer
time lag between data acquisition and display depends on a large number of
factors including the scan rate (NF setting) of the RGA, the host computer’’s
processing speed, and the amount of handshaking activity over the RS232
lines.
x
Before a new scan starts the RGA checks its internal memory to make sure
that no data from any previous scan is pending to be transmitted. If data is
still pending, the RGA must finish transmitting it before the new scan can
start. This process may result in a delay from the time the scan trigger is
received to the time it actually starts. Using the HS1 command and waiting
until the whole scan data stream is transmitted back to the host computer will
minimize the problems that are associated to this feature.
MFparam, param: 1 - M_MAX, *, ?
Description : Final Mass (amu) of mass spectra (Analog and Histogram).
Echo: Query Response
Set the Final Mass value (in amu) for Analog and Histogram scans.
The last ion current transmitted during an Analog or Histogram scan corresponds
the mass-to-charge ratio specified by the MF parameter.
Important : Note that the final mass setting is shared by both histogram and
analog scans, and must be an integer number.
Parameters: Three possibilities :
MFparam, param: 1 - M_MAX: The parameter represents the final scan mass
in amu units. The upper mass limit depends on the RGA model number:
The upper mass limit depends on the SRS RGA model number: M_MAX=100
for RGA100, 200 for RGA200 and 300 for the RGA300 units.
MF* : The final mass value is set to its default value.
Default value: M_MAX=100 for RGA100, 200 for RGA200 and
300 for the RGA300.
MF? : Query the value of final mass to be measured during scans.
Error checking:
Number parameters must be within the specified range, and be integers.
The mass value set by MF must always be greater than or equal to the initial
mass setting of MI or else a parameter-conflict communications error is
generated.
The absence of a parameter (i.e. MF) is treated as a bad-parameter error.
MIparam, param: 1 - M_MAX, *, ?
Description : Initial Mass (amu) of mass spectra (Analog and Histogram).