4
Compound Command Header Omission
When several commands having a common header are combined to form a compound command (for
example,
:SEQuence:TIME:DISCharge1
and
:SEQuence:TIME:CHARge
),
if they are written
together in sequence, the common portion (here,
:SEQuence:TIME:
) may be omitted after its initial
occurrence.
This common portion is called the “current path” (analogous to the path concept in computer file storage), and until it
is cleared, the interpretation of subsequent commands presumes that they share the same common portion.
This usage of the current path is shown in the following example:
Full expression
:SEQuence:TIME:DISCharge1 1,10; :SEQuence:TIME:CHARge 1,20
Compacted expression
:SEQuence:TIME:DISCharge1 1,10; CHARge 1,20
This portion becomes the current path, and can be omitted from the messages immediately following.
The current path is cleared when the power is turned on, when reset by key input, by a colon “:” at the start of a
command, and when a message terminator is detected.
Standard command messages can be executed regardless of the current path. They have no effect upon the current
path.
A colon “:” is not required at the start of the header of a Simple or Compound command. However, to avoid
confusion with abbreviated forms and operating mistakes, we recommend always placing a colon at the start of a
header.
Output Queue and Input Buffer
Output Queue
Response messages are stored in the output queue until read by the controller. The output queue is also cleared in
the following circumstances:
• Power on
Input Buffer
The input buffer capacity of the instrument is 256 bytes.
If 10k bytes are allowed to accumulate in this buffer so that it becomes full, the interface will not accept data beyond
10k bytes.
Note: Ensure that no command ever exceeds 10k bytes.
Summary of Contents for Super megohm SM7110
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