Sterling Scale 825 - Manual (Page 25)

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Revision 4.4 Copyright ©2004Sterling Scale Co., Inc. March 2005
Web Site: www.sterlingscale.com E-mail: [email protected]
COMMUNICATION
Serial Interface
The DW810/825 has the capability of using one of the following serial inteface: RS-232,
RS-422, RS-485, and 20 mA Current Loop. These serial interfaces allow the indicator to be
connected to many different types of serial devices such as printers, computers, and
scoreboards. The standard DW810/825 is equipped with the most common of the serial
interfaces, RS-232.
Output Protocol Format
Baud Rate 150 to 19,200
Parameter
Start Bits 1 Fixed
Date Bits 7 or 8 Parameter
Parity None, Odd, or Even Parameter
Stop Bits 1 Fixed
The format of the serial data is controlled using the following parameters: Baud Rate,
Parity, and Data Bits (See Configuration).
RS-232
The RS-232 interface is the most commonly used of all serial interfaces and is standard on the
DW810/825. It is used in point-to-point communications where the transmission line is less
than 50 feet. If the RS-232 interface is to be used, then the serial interface parameter must be
set to RS-232 (See Configuration).
Flow control may be used with this interface to regulate the flow of data between the
DW810/825 and another serial device. To enable flow control set the Flow Control parameter
to True (See Parameter Setup) and Jumper J8 to CTS (See Jumper Settings). The Clear To
Send (CTS) input must then be connected to the compatible flow control output, usually Data
Terminal Ready (DTR) or Request To Send (RTS). The DW810/825 will now only transmit
when CTS is high.
RS-232 Connector Pin Assignments
Pin
Name Description
01 ZERO External zero
02 Do not connect
03 Do not connect
04 RxD Receive data (input)
05 TxD Transmit data (output)
06 DTR Data Terminal Ready (output)
07 CTS Clear To Send (input)
08 +5VDC +5 Volt DC power
09 GND Digital ground
10 SHIELD Shield
The RS-232 interface connector is “P3” on the circuit board
COMMUNICATIONS
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