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CPLD and Microcontroller RS232 Multiplexer

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huys cobb

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cpld rs232

Can someone give me a suggest on how to built RS-232 multiplexer?

from 1 com port from computer(host) to became 64 com port(slave) or 32 com port(slave)
basicly controller by RTS or DTR and CTS or DSR Host(computer) for decided which com slave active.
The speed from 115.2K to 57.6K or 38.4Kbps.



system block

1.PC Com---max232--MCS-51(DS89C450)--CPLD CY37256P160--MAX208--COMs
Picture
rs232.mux



RTS or DTR choose numbers of slave port(1-32) by sending the strings of data
with Visual Basic,C,Delphi or another PC programmer language RS-232.
The CTS or DSR will pick the numbers of slave port(1-32) which is actived.
(seems like loopback,but the loopback from MCu and CPLD detection)

The MCU serial bit banging program will decode by muxdemux CPLD.

There was Idea from www.circuitmaestro.com.
Unfortunedly the slave output ports only with 8 slave port and 9600bps.

or

2.PC Com---Max232--CPLD CY37256P160--MAX208--COMs
Picture
CPLD

only.jpg


There was idea from Philips AN040 aplication note but it was manual switch.

Anyone Master/guru's suggestion will apreciate.

Thank's
HC
 

huys cobb

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cpld with microcontroller

Thank's

The hardware was already

HC
 

huys cobb

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multiplexer compatible with microcontroller

Maybe someone had built this one?
 

nlksg

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huys cobb said:
Maybe someone had built this one?
Once I saw the multiplexer but is not RS232-RS232. It was Ethernet - RS232 connection.

They use the rabbit controller with ethernet connection and lost of io port. They also connect IO expender chip to extend the number of IO. Rabbit controller itself got few RS232 port and they use the RTS/CTS and chip select to activate specific RS232 output. I have no detail information cause I only saw the prototype few minutes only .

regards
nlksg
 

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