Appendix B

I/O Interface Board

Table B-4 lists the connections on the I/O Board between the Serial Port 1 connector (J7) and the Utility 1Connector (J1).

Table B-4. Serial Port 1 Interface Pin/Signal Descriptions (J7B)

J7

Signal

From

Description

Pin #

 

Onboard

 

 

 

Connector

 

 

 

& Pin #

 

1

DCD1*

J4-1

Data Carrier Detect 1 – Indicates external serial device is detecting a

 

 

 

carrier signal (i.e., a communication channel is currently open). In

 

 

 

direct connect environments, this input is driven by DTR1 as part of the

 

 

 

DTR1/DSR1 handshake.

2

RXD1

J4-3

Receive Data 1 Input – This line is typically held at a logic 1 (mark)

 

 

 

when no data is being transmitted, and is held “Off” for a brief interval

 

 

 

after an “On” to “Off” transition on the RTS1 line to allow the

 

 

 

transmission to complete.

 

RX1-

 

Receive Data 1 Negative – If in RS485 mode, this pin is RX1-.

3

TXD1

J4-5

Transmit Data 1 Output – This line is typically held to a logic 1 when

 

 

 

no data is being sent. Typically, a logic 0 (On) must be present on

 

 

 

RTS1, CTS1, DSR1, and DTR1 before data is transmitted on this line.

 

TX1-

 

Transmit Data 1 Negative – If in RS485 mode, this pin is TX1-.

 

 

 

 

4

DTR1*

J4-7

Data Terminal Ready 1 – Indicates port is powered, initialized, and

 

 

 

ready. Used as hardware handshake with DSR1 for overall readiness.

5

GND

J4-9

Ground

6

DSR1*

J4-2

Data Set Ready 1 – Indicates external serial device is powered,

 

 

 

initialized, and ready. Used as hardware handshake with DTR1 for

 

 

 

overall readiness to communicate.

7

RTS1*

J4-4

Request To Send 1 – Indicates serial port is ready to transmit data.

 

 

 

Used as hardware handshake with CTS1 for low level flow control.

 

TX1+

 

Transmit Data 1 Positive – If in RS485 mode, this pin is TX1+.

8

CTS1*

J4-6

Clear To Send 1 – Indicates external serial device is ready to receive data.

 

 

 

Used as hardware handshake with RTS1 for low level flow control.

 

RX1+

 

Receive Data 1 Positive – If in RS485 mode, this pin is RX1+.

 

 

 

 

9

RI1*

J4-8

Ring Indicator 1 – Indicates external serial device is detecting a ring

 

 

 

condition. Used by software to initiate operations to answer and open

 

 

 

the communications channel.

Notes: The shaded area denotes power or ground. The signals marked with * = Negative true logic.

To implement the two-wire RS485 mode on either serial port, you must tie the equivalent pins together for each port.

For example; on Serial Port 1, tie pin 2 (RX1-) to 3 (TX1-) and pin 7 (TX1+) to 8 (RX1+) at the (DB9) Serial 1 port connector (J7) as shown in Figure B-2. Refer to either table for the specific pins on the port connectors. The RS-422 mode uses a four-wire interface and does not need any pins tied together, but you must select RS-485 in BIOS Setup.

1 2 3 4 5

Standard DB9 Serial Port Connector (Female)

Rear View 6 7 8 9

CM800QkS_13a

Figure B-2. RS-485 Serial Port Implementation

28

QuickStart Guide

CoreModule 800

Page 32
Image 32
Ampro Corporation PCI-104 Signal From Description Pin # Onboard Connector, Figure B-2. RS-485 Serial Port Implementation