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Input Data Format
Numeric data sent to the instrument should be in Ohms or degrees unless stated
otherwise. The value can be in any standard scientific format.
e.g.
3KOHM can be sent as:
3000, 3E3, 3.000E3, 0.3E4 etc.
The units are not sent.
Output Data Format
Non- Measurement queries
ASCII character string
Measurement queries
IEEE
SDDDD.DDDESDD <lf>
RS-232
SDDDD.DDDESDD <cr><lf>
Where
S = sign (+/-)
D = decimal digit (0-9)
E = Exponential
<cr> = carriage return character
<lf> = linefeed character
Note: In IEEE mode the EOI line is also asserted with the transmission of the <lf>
terminator.
Measurement queries always return values expressed in Ohms or Degrees, but the
units are omitted. Resistance values are returned with engineering exponents
reflecting the resolution and units displayed on the LCD screen.
e.g.
Display
Returned Value
30.321
Ω
30.321
(30
Ω
range)
29.657 K
Ω
29.657E+3
(30K
Ω
range)
106.45 m
Ω
106.45E-3
(200m
Ω
range)
If a query (?) command results in a “command” or “execution” error, the error value
+9.90E+37 is sent to the output buffer.
Input Message Terminators
In RS-232 mode, all messages sent to the in strument must terminate with either a
<lf> character or a <cr> character. It is also permi tted to send both <cr><lf> to
terminate a message; the <lf> is ignored.
For IEEE-488 mode, messages can be terminated in one of two ways;
- by sending a <lf> character at the end of the message
- by asserting the EOI line with the last character sent
It is also permitted to combine these, and assert EOI when sending the <lf>
character.
Message termination always forces the command path back to the root-level ready for
the next command message.