Reference And Phase - Stanford Research Systems SR810 Manual

Remote Programming
REFERENCE and PHASE COMMANDS
PHAS (?) {x}
FMOD (?) {i}
FREQ (?) {f}
RSLP (?) {i}
HARM (?) {i}
SLVL (?) {x}
The PHAS command sets or queries the reference phase shift. The
parameter x is the phase (real number of degrees). The PHAS x
command will set the phase shift to x. The value of x will be rounded to
0.01°. The phase may be programmed from -360.00 ≤ x ≤ 729.99 and
will be wrapped around at ±180°. For example, the PHAS 541.0
command will set the phase to -179.00° (541-360=181=-179). The
PHAS? queries the phase shift.
The FMOD command sets or queries the reference source. The
parameter i selects internal (i=1) or external (i=0).
The FREQ command sets or queries the reference frequency. The
FREQ? query command will return the reference frequency (in internal or
external mode).
The FREQ f command sets the frequency of the internal oscillator. This
command is allowed only if the reference source is internal. The
parameter f is a frequency (real number of Hz). The value of f will be
rounded to 5 digits or 0.0001 Hz, whichever is greater. The value of f is
limited to 0.001 ≤ f ≤ 102000. If the harmonic number is greater than 1,
then the frequency is limited to nxf ≤ 102 kHz where n is the harmonic
number.
The RSLP command sets or queries the reference trigger when using
the external reference mode. The parameter i selects sine zero crossing
(i=0), TTL rising edge (i=1), or TTL falling edge (i=2). At frequencies
below 1 Hz, the TTL reference must be used.
The HARM command sets or queries the detection harmonic. This
parameter is an integer from 1 to 19999. The HARM i command will set
the lock-in to detect at the ith harmonic of the reference frequency. The
value of i is limited by ixf ≤ 102 kHz. If the value of i requires a detection
frequency greater than 102 kHz, then the harmonic number will be set to
the largest value of i such that ixf ≤ 102 kHz.
The SLVL command sets or queries the amplitude of the sine output.
The parameter x is a voltage (real number of Volts). The value of x will
be rounded to 0.002V. The value of x is limited to 0.004 ≤ x ≤ 5.000.
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