EXFO FTB-500 (Window XP) - Handbuch (Seite 449)

COM Properties and Events
FTB-500 441
Properties
Read
Description With this method you can retrieve all the data
from the device output queue in a UNICODE
format.
Syntax object.Read
Parameter(s) None.
Response(s) A string value (in UNICODE format).
Notes This method must be used in conjunction with
the Write method. Always ensure that a query
has been previously sent before attempting to
read a response from the output queue.
To properly set the data format, send the
following command (using the Write method):
FORM:DATA<wsp>ASCII <number_of_digits>
where <number_of_digits> corresponds to the
number of digits after the decimal point that you
require.
Remember that the retrieved data will have to be
converted to a numeric format before you can
use it in calculations, for example.
Possible error(s) Timeout: This error will occur if the allowed
delay has expired before the preceding Write
operation could send a response to the output
queue. For information on timeout setting, see
Initialize on page 443.
QueryUnterminated: This error will occur if the
output queue is empty (for example, no query
has been made previously).