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PG-200 Operation Manual
Version 2.D
A complete description the interface functions is contained in Appendix A. The Linkable
Object functions are contained in a subdirectory called OBJ. The WinView/WinSpec
Interface functions are built into the WinView/WinSpec software.
Error Checking
There is no error checking in the Linkable Object format. Reasonable values are
expected to be provided by the user. In the WinView/WinSpec format, the only error
checking that exists is used to check for the proper number of parameters.
The PG-200 will correct for unreasonable values. For example, if a width of 100
milliseconds was programmed, an error message would appear on the Front Panel
Display stating the range of values permitted. However, there is no provision to send an
error flag back to the sending program.
The reason that error checking of values has been omitted is because many values are
dependent on other values. For example, by definition, width plus delay are not allowed
to exceed 80 milliseconds. This means that in order to determine if a width value is
excessive, the communication program would have to know delay value. Also, suppose a
width value of 10 milliseconds was programmed and the user wanted to set an internal
trigger frequency of 1000 Hz (1 millisecond period). This is obviously a conflict. There
are many cases similar to these which could cause conflicts, so it is up to the user to send
reasonable values.
Special Considerations
Initializing the serial port
In the WinView/WinSpec and Linkable Object, it is the responsibility of the programmer
to ensure that the serial port is initialized. There is an init_serial () function that can be
used for this purpose. The init_serial () function sets the required serial parameters of
9600 Baud, 8 characters, 1 Stop bit and Parity disabled.
Changing the pulse width
There are cases where changing a pulse width can cause the PG-200 to adjust its internal
high voltage supply to a new value. This can take up to 5 seconds and although no
commands will be missed, it should be noted that no pulsing can occur during this time.
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