The AD279A solution can support up to four 16-port RS-232 port modules. The port modules provide either DB25 Male RS-232 serial ports or RJ45 RS-232 serial ports.

Pin-Layout and Port Interface Differences between A6748A/A6749A and AD278A/AD279A PCI MUX Serial Ports

Table 5 describes the pin-layout differences between A6748A/A6749A and AD278A/AD279A PCI MUX serial ports.

Table 5: A6748A/9A and AD278A/9A RJ45 RS232 Pin-Layout Comparison

 

AD278A / AD279A Serial MUX

A6748A/A6749A Serial MUX

 

Solution

 

Solution

 

Interface type

RJ 45 RS 232 ports

 

RJ 45 RS 232 ports

 

Pin # 1

RI

 

Ring Indicator

RI

 

Ring Indicator

Pin # 2

DSR

 

Data Set

RTS

 

Request to

 

 

 

Ready

 

 

Send

Pin # 3

RTS

 

Request to

DTR

 

Data Terminal

 

 

 

Send

 

 

Ready

Pin # 4

GND

 

Chassis

RXD

 

Received Data

 

 

 

Ground

 

 

 

Pin # 5

TXD

 

Transmitted

GND

 

Ground

 

 

 

Data

 

 

 

Pin # 6

RXD

 

Received Data

TXD

 

Transmitted

 

 

 

 

 

 

Data

Pin # 7

SG

 

Signal Ground

GND

 

Signal Ground

Pin # 8

CTS

 

Clear to Send

DCD

 

Data Carrier

 

 

 

 

 

 

Detect

Pin # 9

DTR

 

Data Terminal

CTS

 

Clear to Send

 

 

 

Ready

 

 

 

Pin # 10

DCD

 

Data Carrier

DSR

 

Data Set

 

 

 

Detect

 

 

Ready

The AD278A/AD279A PCI MUX solution provides Male DB25 RS-232 serial ports, whereas the A6748A/A6749A PCI MUX solution provides Female DB25 RS-232 serial ports. The DB25 pin-outs for the AD278A/AD279A PCI MUX solution and A6748A/A6749A PCI MUX solution are the same.

Cabling Cases and Solutions

This section discusses instances of incompatibility between A6748A/A6749A and AD278A/AD279A PCI MUX solutions. It also discusses solutions to resolve these incompatibilities. Table 6 lists scenarios of incompatibility that prevent successful migration from A6748A 8-port RJ45 solution to the AD278A/AD279A PCI MUX solution. It also describes methods to resolve issues of incompatibility.