Ametek 7230 Instruction Manual page 118

Chapter 6, COMPUTER OPERATION
DD [n]
ST
USBTERM [n]
N
6-32
bit number bit negated
0 data = 7 bits
1 no parity bit
2 even parity
3 echo disabled
4 prompt disabled
Define delimiter control
The value of n, which can be set to 13 or from 32 to 125, determines the ASCII value
of the character sent by the lock-in amplifier to separate two numeric values in a
two-value response, such as that generated by the MP (magnitude and phase)
command.
Report status byte
Causes the lock-in amplifier to respond with the status byte, an integer between 0
and 255, which is the decimal equivalent of a binary number with the following bit-
significance:
Bit 0 Command complete
Bit 1 Invalid command
Bit 2 Command parameter error
Bit 3 Reference unlock
Bit 4 Output overload - read overload byte to determine location
Bit 5 New ADC values available after external trigger
Bit 6 Input overload
Bit 7 Data available
Set/read USB terminator
The value of n sets the USB terminator according to the following table:
n Function
0 A null character (ASCII 0)
1 A null character (ASCII 0), followed by a byte representing the value of the
status Byte (table 6-1), followed by a byte representing the value of the Overload
Byte (table 6-1)
Report overload byte
Causes the lock-in amplifier to respond with the overload byte, an integer between 0
and 255, which is the decimal equivalent of a binary number with the following bit-
significance:
Bit 0 X(1) channel output overload (> ±300 %FS)
Bit 1 Y(1) channel output overload (> ±300 %FS)
Bit 2 X2 channel output overload (> ±300 %FS)
Bit 3 Y2 channel output overload (> ±300 %FS)
Bit 4 CH1 output overload
Bit 5 CH2 output overload
Bit 6 CH3 output overload
Bit 7 CH4 output overload
bit asserted
data = 8 bits
1 parity bit
odd parity
echo enabled
prompt enabled