Q

The Q command returns the output reading in units of volts. For an input signal of 50 ∝ V on a full scale sensitivity of 100 ∝ V, the Q command will return the string "50.00E-6". The parameter read is the same as that being shown on the output display and can be changed with the S command.

R {n}

If n is included, the R command sets the reference input trigger mode. If n is absent, the trigger mode is returned.

nMode

0 Positive

1 Symmetric

2 Negative

S {n}

If n is included, the S command selects the parameter shown on the analog meter and output digital display as well as the output BNC. If n is absent, the parameter being displayed is returned.

nDisplay

0 X

1 Offset

2 Noise

T m {,n}

The T command sets and reads the status of the time constants. If m is "1", the pre time constant is selected, if m is "2", the post time constant is selected. The parameter m is required. If n is included, the T command sets the selected time constant. If n is absent, the setting of the selected time constant is returned.

n Pre Time Constant (m=1)

1

1

mS

2

3

mS

310 mS

430 mS

5100 mS

6300 mS

71 S

83 S

910 S

1030 S

11100 S

nPost Time Constant (m=2)

0 none

1 0.1 S

2 1 S

U m {,n}

The U command sets and reads the unit's ROM calibration bytes. m is the address offset of the byte, 0-255. If n is absent, the value of the addressed calibration byte is returned. If n is included, the addressed calibration byte is set to the value of n, 0-255. The new value will be in effect until the power is turned off or a reset command is issued. Use of this command is not recommended.

V {n}

If n is included, the V command sets the GPIB SRQ (service request) mask to the value n. If n is absent, the value of the SRQ mask is returned.

W {n}

The W command sets and reads the RS232 character wait interval. If n is included, the SR510 will wait n*4 mS between characters sent over the RS232 interface. This allows slow computer interfaces to keep up. n can range from 0 to 255. If n is absent, the wait value is returned. The wait interval is set to 6 on power-up.

X n {,v}

n designates one of the 6 general purpose analog ports located on the rear panel. If n is 1,2,3, or 4, the X command will return the voltage on the designated analog input port (X1-X4) in volts. If n is 5 or 6, then v may also be sent. If v is included, the designated analog output port (X5 or X6) will be set to v volts where v has the range -10.24V to +10.24V. If v is absent, the output value of the selected port is returned. On power-up, port X5 is the ratio output. An "X 5" command will read the ratio output. An "X 5" command with the parameter v will set port X5 to v volts, overriding the ratio output. Port X5 will return to the ratio output on power-up or reset.

Y {n}

The Y command reads the status byte. (See below for a definition of the Status Byte.) n designates one bit, 0-7, of the status byte. If n is included, the designated bit of the status byte is returned. The bit which is read is then reset. If n is absent, the value of the entire byte is returned and all status bits are then reset. This status byte may also be read over the GPIB using the serial poll command.

Z

The Z command causes an internal reset. All settings return to their default values. The ERR

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