HP 16501A LOGIC, Programmer'S Manual

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Writing to
\system\program
from a Program
You can send commands to the HP 16500C program file from a program
running on your PC or workstation. The basic procedure is to open the
program file and send text strings containing the commands to the file. In C,
you can use the
fwrite
or
putstr
commands to write text strings to the
program file.
Your operating system may buffer the commands before sending them to the
HP 16500C system. To prevent this, you may need to empty the buffer after
each command. In C, you can use the
flush
command to empty the buffer.
Queries
Responses to queries appear as text strings in
\system\program
. To
retrieve information from queries, create a text buffer, open the
program
file
and read the contents of the file into the buffer. In C you can use the
fread
or
getstr
commands to read the contents of the file into the buffer.
Whenever you send queries to the HP 16500 system, you will need to pause
your program for a short time, to allow the system to process the query
before you attempt to read the response. A time equal to or slightly greater
than the file timeout is sufficient.
Resetting the File Pointer
Whenever you change from reading
\system\program
to writing to it, or
from writing to reading, you will need to reset the file pointer to the
beginning of the file. In C, you can use the
rewind
command to reset the
pointer, or you can close the program file, then immediately re-open it.
Programming Over LAN
Writing to
\system\program
from a Program
4–8