Chapter 5: RS-232 Connections/Operation

The DB-9 male connectors on the card are configured as standard RS-232 (DTE) serial ports. Table 3 shows the signal names and pin numbers.

Table 3: RS-232 Pinouts

Name

Description

Direction

DB9M

 

 

(DTE)

Pin

 

 

 

 

DCD

Data Carrier Detect

Input

1

RD

Receive Data

Input

2

TD

Transmit Data

Output

3

DTR

Data Terminal Ready

Output

4

GND

Signal Ground

------

5

DSR

Data Set Ready

Input

6

RTS

Request to Send

Output

7

CTS

Clear to Send

Input

8

RI

Ring Indicator

Input

9

RS-232 Operation

RS-232 signal lines are referenced to Ground and each signal can alternate above and below ground by the rated voltage (see Specifications for RS-232 Transmitter/Receiver). Typical input voltage levels range from -11 to -3 Volts or +3 to +11 Volts.

The primary RS-232 signals are Transmit (Tx) and Receive (Rx), so together with Ground, they make a “3-wire” interface.

The RTS and CTS signals are Handshaking lines used to indicate to the other device that data can be sent or received. These lines may be enabled or disabled on a byte-by-byte basis and are used to prevent buffer overrun or the loss of data. Auto hardware support.

Two secondary Handshaking signals are DTR and DSR. They are usually enabled when the device is powered up and the port is open. They may be used for flow control by some devices instead of RTS and CTS.

DCD is used by a modem to indicate Carrier to the computer so data can be sent/received. RI is output by a modem to indicate that the phone or FAX line has a incoming call, so it can be handled.

42

Chapter 5

Documentation Number 3PCI2-0903 Manual

B&B Electronics Mfg Co – 707 Dayton Rd - PO Box 1040 - Ottawa IL 61350 - Ph 815-433-5100 - Fax 815-433-5104 B&B Electronics Ltd – Westlink Comm. Pk. – Oranmore, Galway, Ireland – Ph +353 91-792444 – Fax +353 91-792445

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B&B Electronics 3PCI2 manual RS-232 Connections/Operation, RS-232 Pinouts Name Description Direction, RS-232 Operation
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3PCI2 specifications

B&B Electronics has long been a leader in the field of industrial networking solutions, and their 3PCI2 serial communication card exemplifies this expertise. The 3PCI2 is a dual-port PCI serial communications interface designed to provide PC systems with reliable and efficient connectivity to serial devices. This card is particularly useful for applications requiring multiple serial device connections, making it a favorite among developers and engineers.

One of the main features of the 3PCI2 is its ability to support two independent, programmable serial ports. These ports can handle RS-232, RS-422, or RS-485 communication, allowing for flexible connection options based on specific application needs. This versatility is essential in industries such as factory automation, transportation, and telecommunications, where different devices may require distinct communication standards.

The 3PCI2 utilizes advanced technology that ensures high-speed data transfer rates, reaching up to 115.2 kbps. This speed, combined with the card's reliable architecture, minimizes latency and ensures smooth communication between the PC and connected devices. Additionally, the use of direct memory access (DMA) capabilities enhances performance by allowing data to be transferred directly between the serial ports and memory without involving the CPU, thereby reducing system overhead.

Another notable characteristic of the 3PCI2 is its plug-and-play compatibility. Installation is straightforward, as it can be easily inserted into any available PCI slot on a standard PC motherboard. The card is also supported by a comprehensive driver package compatible with various operating systems, ensuring seamless integration into existing systems.

Furthermore, the 3PCI2 features high-quality signal integrity and noise immunity, which are critical in industrial environments where electromagnetic interference can impact performance. The card is designed with robust components to withstand harsh conditions, making it reliable for long-term use in demanding applications.

Overall, B&B Electronics’ 3PCI2 serial communication card stands out for its combination of features, versatile connectivity options, and robust performance. Its ability to provide reliable, high-speed communication in a dual-port configuration makes it an excellent choice for industries that rely on effective serial communication solutions. As technology continues to advance, the 3PCI2 remains a relevant and dependable option for developers looking to enhance their systems with reliable serial connectivity.
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