Keysight 53210A, Руководство пользователя

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7 Formats and Data Flow
196 Keysight 53210A User’s Guide
2 all readings are stored in an internal counter format - the programmed format
(
FORMat
subsystem) is set when readings are transferred to the output buffer.
3 if reading memory overflows the first (oldest) readings are overwritten and the
‘Reading Mem Ovfl’ bit (14) in the Questionable Data Register is set. The most
recent measurements are retained.
Output Buffer
Data is available to the PC over the LAN, USB, and GPIB interfaces once it is in the
output buffer ( Figure 7-1 ). The following section explains how readings are
transferred from memory to the buffer. If during a transfer the output buffer fills,
command execution is paused until readings are removed by the PC - creating
room in the buffer. No readings are lost.
Transferring Readings from Memory to the Output Buffer
The following commands transfer readings from volatile reading memory to the
buffer.
READ?
- is equivalent to executing
INITiate:IMMediate
directly followed by
FETCh?
. With
READ?
, once all readings specified by
TRIGger:COUNt
and
SAMPle:COUNt
are complete and in memory, they are instantaneously read into the
output buffer ( Figure 7-1 ).
If the data format is REAL (
FORMat
subsystem), each block of readings generated
by
READ?
is preceded by an IEEE 488.2 Indefinite-Length block header ( Table 7-1 ).
As such, when sending multiple commands in a single command string,
READ?
should always be the last command in the string.
READ? Example
// frequency meas of 500 kHz signal with uHz resolution
CONF:FREQ 500E3, 1E-6, (@1) // configure counter
TRIG:COUN 1 // set trigger count
SAMP:COUN 10 // take 10 readings
READ? // read readings when complete