Multiplexing real RS232 signals.

Archiver

Is it possible to let a Maxim MUX , (e.g Max358) multiplexing real
RS232-level signals?

I was hoping to control the communication between 6 different serial
devices, and let the stamp monitor the incoming data on the BS2
serial port 16.

The Max 358 has eight +/- 15 volt analog input ports. But can the IC
be used to switch real serial communication (1200-9600 baud) What
about rise and fall time?

Stein.

Archiver

The problem you can run in to with the Stamp is
that it can only do one thing at a time. To receive
an RS-232 signal, you need to 'listen' to the line
for 10 bit periods -- and it has to be the 'right'
10 bit periods -- from the start bit to the stop
bit. If you don't know when these times are, you
can 'start' listening in the middle of a byte --
which means you won't get that byte.

When the Stamp is in a SERIN, that's all it can
do, is receive on one line. Any other lines are
ignored. Similarly, if you use the MUX approach,
you can only monitor one line at a time.

If that's what you want (AND you have a +- 15 volt
supply for the Mux) (AND the mux will do 9600 baud
signals -- hard to tell from the spec sheet) then
the MAX358 should work.

--- In basicstamps@yahoogroups.com, "stein_frostad"
<Stein_Frostad@m...> wrote:
> Is it possible to let a Maxim MUX , (e.g Max358) multiplexing real
> RS232-level signals?
>
> I was hoping to control the communication between 6 different
serial
> devices, and let the stamp monitor the incoming data on the BS2
> serial port 16.
>
> The Max 358 has eight +/- 15 volt analog input ports. But can the
IC
> be used to switch real serial communication (1200-9600 baud) What
> about rise and fall time?
>
> Stein.