Instrument Identification - IBM 7220 Instruction Manual

byte is accessed by performing a serial poll.
Bit 0 Command complete
Bit 1 Invalid command
Bit 2 Command parameter error
Bit 3 Reference unlock
Bit 4 Overload
Bit 5 New ADC values available after external trigger
Bit 6 Asserted SRQ
Bit 7 Data available
N Report overload byte
Causes the lock-in amplifier to respond with the overload byte.
Bit 0 not used
Bit 1 CH1 output overload (> ±120 %FS)
Bit 2 CH2 output overload (> ±120 %FS)
Bit 3 Y output overload (> ±300 %FS)
Bit 4 X output overload (> ±300 %FS)
Bit 5 not used
Bit 6 input overload
Bit 7 reference unlock
MSK [n] Set/read service request mask byte
The value of n sets the SRQ mask byte in the range 0 to 255
REMOTE [n] Remote only (front panel lock-out) control
Allowed values of n are 0 and 1. When n is equal to 1, the lock-in amplifier enters
remote only mode in which the front panel control functions are inoperative and the
instrument can only be controlled with the RS232 or the GPIB interfaces. When n is
equal to 0, the front panel control functions normally.

6.4.11 Instrument Identification

ID Identification
Causes the lock-in amplifier to respond with the number 7220.
REV Report firmware revision
Causes the lock-in amplifier to respond with the firmware revision number. This gives
a four line response which the controlling program must be able to accept.
VER Report firmware version
Causes the lock-in amplifier to respond with the firmware version number. The
firmware version number is the number displayed on the front-panel RS232 SETUP 3
screen.
Chapter 6, COMPUTER OPERATION
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