HP E4418B Programming Manual page 238

CALibration Subsystem
CALibration[1|2]:RCALibration <Boolean>
Error Message
When CAL[1|2]:RCAL is ON and the sensor currently connected to the
appropriate channel (A or B) has not been zeroed and calibrated, then any
SCPI command which would normally return a measurement result (for
example, FETC?, READ?, MEAS? etc) will not return a result but will
generate the error -230, "Data corrupt or stale; Please zero and Cal."
Once the sensor has been zeroed and calibrated the commands which
return measurement results will function normally.
HP E4418B/E4419B Programming Guide 4-11