[REBOL] Re: Serial Communications - SUCCESS!!!
From: greggirwin:mindspring at: 26-Feb-2002 17:48
<< TO DO:
My next hurdle is to create a loop to identify the specific NMEA
sentences.
That funny stuff that looks like [$GPGLL] is what defines a particular
data sentence in NMEA.
Once I can identify a sentence by the first few characters (in this case
a $ sign followed by five letters I can shunt them off for processing.
Any pointers in this regard will not be spurned given my recent
experience.
The first pitfall I see is having Rebol mistake this $ sign for a money
token
and wrap me up in some data type dungeon. >>
Well, we can do some simple things to start with.
First, you can split the data string up into fields, assuming that's
helpful:
>> b: parse/all {$GPGLL,4330.038,N,08030.681,W,220800,A*3B} ","
== ["$GPGLL" "4330.038" "N" "08030.681" "W" "220800" "A*3B"]
Next, you could see if the first field starts with "$", and chop the "$" off
of it:
>> if b/1/1 = #"$" [b/1: next b/1]
== ["GPGLL" "4330.038" "N" "08030.681" "W" "220800" "A*3B"]
Now, you can look at the first field (i.e. b/1) to see what your code is so
you can branch and process accordingly.
HTH!
--Gregg
