A slight deviation from the original topic...

I have about a dozen instruments with RS232C/D interfaces and one PC
with one serial port. Is there an easy and cheap network that can be
inserted between the PC and instruments to allow addressing and
multidrop configuration. If not, i plan to implement a PIC based
packet network to connect all instruments, configuration as follows:


                        [RS484 Half or Full Duplex Backbone]
PCSERIAL---NODEMASTER---------------------------------------
           (ADDR  00)     |          |          |          |
                        SLAVE      SLAVE      SLAVE      SLAVE
                        (01)        (02)      (03)        (nn)
                        RS232      RS232      RS232      RS232
                      [INSRUM]    [INSTRUM]  [INSTRUM]  [INSTRUM]

Rather than reinvent the wheel so to speak, can any one suggest a
solution.

Nino Benci


******************************************************
* Antonio (Nino) Benci                               *
* Electronics & Computing Services Manager           *
* Monash University - Dept of Physics                *
* Wellington Rd, Clayton. 3168                       *
* Victoria, Australia.                               *
* TEL - 61 3 9905 3649, FAX - 61 3 9905 3637         *
* EMAIL - nino.benci@sci.monash.edu.au               *
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