serialControlString
Dar Scott
dsc at swcp.com
Tue Nov 25 17:32:22 EST 2003
On Tuesday, November 25, 2003, at 06:34 AM, Thomas J McGrath III wrote:
> I think you guys forgot that I am way new to REV, so syntax is
> tripping me up big time. I have been able to communicate TO the device
> but not get any desired result from the device.
> Do I need to read from device in order to get the result or should the
> result be a part of the write to process being returned ? I want to
> learn more but this is way beginner stuff concerning the proper syntax
> and expected results.
I have used the word 'result' in a particular way and there may be
confusion.
Many commands will set an error value. Each serial command will set an
error value. If all is well, it is empty. Otherwise it is a text
value that might be helpful.
The function result() returns that value. An alternate syntax is 'the
result'.
I also look at the the value returned by sysError(), which often
returns the error code returned by the underlying system. That might
not be meaningful to you, but it might help those on the list who
provide advice.
This is independent of getting the response from the device. (I'm
using the word "response" to avoid saying "result" which is ambiguous,
because of the result() function.)
To get the response from the device, read from the device. The
characters read will be in the local variable named 'it'. Thus, with a
read, you can look at 'it' and 'the result'. The first will be the
data from the MacBrick and the second will be some status information
about the read (not about the MacBrick).
If you think you are actually writing to the equipment, then try
something like this after that in your script (where macBrickPort is
defined earlier):
wait 2 seconds
read from driver macBrickPort until empty
put "response = " & quote & it & quote & LF into report
put "result (error) = " & quote & the result & quote & LF after
report
put "system error = " & the sysError & LF after report
put report
Dar Scott
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