Avtech AV-1011-C-OP1 Instructions Manual page 20

OP-1 Operating Instructions
2.2 Command Interpretation
The command may utilize the defined single letter acronym, or may be expanded to
a longer word to make the control program easier to understand. This is because letters
following the defined acronym letter are ignored. For example, a command of "V 70.2"
will result in exactly the same result if the command is sent as "Voltage of output pulse =
70.2". However, it is mandatory that the first letter of each command be one of the five
defined acronyms.
Acronyms are case insensitive, for example, "R" or "r" are the same.
The number following the acronym letter may be any number in the range
specified, however, the number of significant digits are limited to one part in 255 (for 8
bits of output resolution). For example, amplitude values of 12.82, 12.83 or 12.82145
will all result in the same output. (Note that output resolution and accuracy are not
necessarily the same).
Leading or trailing zeros in numbers will be ignored.
Numbers expressed in "exponential" format will NOT be interpreted correctly. For
example, 3e+3 will be interpreted as 3, not as 3000.
The range of the specified values must be as specified for the equipment. Numbers
outside the range will be ignored.
If desired, trailing text may be added to make the control program easier to
understand, since it will be ignored. For example, a command of "width =77" will result in
the same output as the command " width = 77 microseconds".
The term "Delay" is used to specify the duration of the delay between the trigger
output pulse and the occurrence of the actual output pulse. The term "Advance" similarly
refers to the amount of time the trigger pulse will occur prior to the output pulse.
If an invalid command is sent, the unit will ignore the command and the previous
value will remain unchanged. If an "out-of-range" value is sent, the unit will also ignore
the command.
The polarity of the output pulse is controlled by sending the letter P followed by a
+ sign for positive or a - sign for negative.
2.3 Typical Command Sequence Interpretation
Assume the following commands are sent using the computer, using the
appropriate command structure as specified for the user's GPIB controller. Note that the
default GPIB address is eight.
R=1000
W=30
V= 30
A=10
P=+
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