Keithley 4200A-SCS

Section
9: Keithley External Control Interface (KXCI) Model 4200A-SCS Parameter Analyzer Reference Manu
al
9-54 4200A-901-01 Rev. C / February 2017
Measure mode
Z =
V
Voltage
I
Current
Reading (mantissa and exponent)
±N.NNNN E±NN
Scientific notation for the reading exponent:
E+00 = 0
E-03 = 10
-3
(m)
E-06 = 10
-6
(µ)
E-09 = 10
-9
(n)
E-12 = 10
-12
(p)
Status byte and serial polling
The status byte is an 8-bit register that provides status information on instrument operation. When a
particular operating condition occurs, one or more bits of the status byte sets.
You can use serial polling to read the status byte.
The following sections describe the status byte and serial polling.
Status byte
The status byte is an 8-bit register that provides status information on instrument operation. When a
particular operating condition occurs, one or more bits of the status byte sets. The status byte register
is shown in the following table.
Status Byte Register
Bit B7 B6 B5 B4 B3 B2 B1 B0
Condition
— RQS — Busy — —
Syntax
Error
Data
Ready
Binary Value
—
0/1
—
0/1
—
—
0/1
0/1
Decimal Weight
—
64
—
16
—
—
2
1
The four used bits of the status byte register are described in the following topics.
Bit B0, Data Ready
This bit sets (1) when all measurements are completed and data is ready to be output on the GPIB.
Any of the following actions clear (0) bit B0:
• Clears (0) when the data transfer starts.
• Clears (0) when the BC (buffer clear) command is sent to the 4200A-SCS.
• Clears (0) when the 4200A-SCS is serial polled.