newlispfanclub.alh.net

When running the following code:

; Initialization
(define (com-init)
(exec "mode COM1 BAUD=9600 PARITY=O DATA=8 STOP=1"))

; Getting data from COM-port
(define (start-listening)
(local (hndl buff)
(set 'hndl (open "COM1" "r"))
(read hndl buff 40 (char 0x0D))
(close hndl)
(int (-12 5 buff))))

(com-init)

(if (catch (start-listening) 'result)
(println "Message: " result)
(println "no link"))
--------------------------------------------------
My message returns nil.

I assume that it is looking for printable characters, but how can I capture the hex of the message.

My ultimate goal is to write a Modbus module for newlisp. That would allow me to use it at work as most of the equipment we use supports Modbus.

Please forgive me, I am so new and constantly over my head.

I see that the result symbol is only capturing true and not the message.

no, no, the 'result variable actually is receivng the return value of the expression and the whole 'catch' expression returns true.
what probably is happening in your case is, that (int (-12 5 buff)) returning nil because the contents of (-12 5 buff) is not a number. If buff contains 0 characters it will stop printing at that place. You could insert a (print (-12 5 buff)) to see the contents. Or do a (print (map char (explode (-12 5 buff)))) to see what's in that piece of buff. Or inspect the entire buffer with (println (map char (explode buff)))