[comp.sys.mac.comm] Funky use of serial ports on SE/30

rob@cs.mu.oz.au (Robert Wallen) (08/02/90)

Before I ask the question, here is an answer I would prefer not to get.
"Use the Communication Toolbox".

Having that out of the way, I have a need for a custom application which can
take serial input from a modem, display most of it as though it were VT100
but recognise certain escape sequences and direct all traffic from that point
on to the printer port (until another sequence is spotted).

The basic task is to allow me to use a Tektronix 4107 next to my SE/30, with
the Mac showing text and the Tek doing graphics...

Programmers:  I have a skeleton VT100 already built and was thinking about
hacking the extra sequences in when another idea occurred which I thought I
would run past the net for feedback.  Email please, Ill summarise.

How hard would it be to write an INIT/cdev to replace the standard .AIN/.AOUT
drivers with a custom version which watches the data that is passes to programs.
It lurks inside _Read/_Control/_Status calls and whenever it sees data but is
in the passthrough mode, it redirects the data to the Printer port and fakes
a return that says 'no data'.  That way, I can use any of the existing VT100s
around.  Can anyone see anything thats going to make this a nightmare to
implement?

kazim@Apple.COM (Alex Kazim) (08/04/90)

In article <3104@murtoa.cs.mu.oz.au> rob@cs.mu.oz.au (Robert Wallen) writes:
>Before I ask the question, here is an answer I would prefer not to get.
>"Use the Communication Toolbox".

Well, this isn't my answer, but I am a little confused as to why it isn't
the one to hear.

From the description, it seems as though you could have a simple application
that uses the CommToolbox, and use _CMAddSearch to look for the escape
sequences.  When the search completes, instead of routing data to the
terminal tool, you send it to the Tek.

Unless, of course, you want to do things the hard way.  

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Alex Kazim, Apple Computer
Hop on the bus, Gus
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