DS74 Serial I/O Module

Status

Displays the current configuration of each I/O port.

+

----

+------

+

-----------------Device

+------

+

------

+

------

+------

+---------

+----

+----

+

PortDevice

Baud Word Stop

ParityHandshakeLineDrive

 

Type

Name

Rate Size Bits

DTR

RTS

+

----1

+------

+

-----------------

+------

+

------8

+

------1

+------

+---------

+----

+----

+

RPC

Device A

9600

None None

HI

HI

+

----2

+------

+

-----------------

+------

+

------8

+

------1

+------

+---------

+----

+----

+

RS232 Device B

9600

None None

HI

HI

+

----3

+------

+

-----------------

+------

+

------8

+

------1

+------

+---------

+----

+----

+

RS232 Device C

9600

None None

HI

HI

+

----4

+------

+

-----------------

+------

+

------8

+

------1

+------

+---------

+----

+----

+

RS232 Device D

9600

None None

HI

HI

+

----

+------

+

-----------------

+------

+

------

+

------

+------

+---------

+----

+----

+

Strike ENTER to continue

Serial Port Configuration

Since the DS74 I/O modules use different serial port configurations. Handshaking, Baud Rate, Word Size, Stop Bits, and Parity can all be configured through the HOST module using the menus. The default settings are 9600bps, 8 data bits, no parity, one stop bit, RTS and DTR High.

Select 2), the peripheral module responds asking for a port number:

Enter Serial Port Number (? = Help, ENTER = Exit) :1

Type the port number, press <cr> and the unit responds:

+

----+

------+

-----------------Device

+------

+------

+------

+------

+---------

+----

+----

+

PortDevice

Baud Word Stop

ParityHandshakeLineDrive

Type

Name

Rate Size Bits

DTR

RTS

+

----+

------+

-----------------

+------

+------

+------

+------

+---------

+----

+----

+

1

RS232 Device A

9600 8

1

None None

HI

HI

+

----+

------+

-----------------

+------

+------

+------

+------

+---------

+----

+----

+

 

Handshaking

 

1

 

 

 

 

 

 

 

Baud

Rate

 

2

 

 

 

 

 

 

 

Word

Size

 

3

 

 

 

 

 

 

 

Stop

Bits

 

4

 

 

 

 

 

 

 

Parity

 

5

 

 

 

 

 

 

 

RTS Line Driver Inactive State...

6

 

 

 

 

 

 

 

DTR Line Driver Inactive State...

7

 

 

 

 

 

 

Enter Request :1

Handshaking

For a simple communication between modems three connected lines are needed: TX, Rx, and Ground. For the data to be transmitted, both sides have to be clocking the data at the same baud rate. While this method is sufficient for most applications, it is limited in being able to respond to problems such as the receiver getting overloaded. This is where serial handshaking can help.

Select 1), for the Handshaking menu, Default is None, the Host module responds with the following:

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Bay Technical Associates DS74 manual Status, Serial Port Configuration, Handshaking