Specifications

Appendix II

RS-232 Serial Data Communications

Your Setra Easy Count comes equipped with a bidirectional RS-232 interface

using a default baud rate of 2400 and no parity. Users who are interfacing a

scale to the Auto Count 200 or to an optional serial printer should follow the

installation instructions in the Easy Count Technician’s Guide or the Auto

Count 200 manual.

The RS-232 Interface Hardware

Although Setra scales can communicate with almost any RS-232 device, the

built-in interface does not include the complete protocol. Only the transmit

and receive lines of the standard interface are used. This should not present

any interfacing problems in most applications.

The data format is: 1 start bit

8 data bits including parity

1 stop bit

10 bits per frame (framing errors ignored)

Note: The scale will transmit using the parity selected; however it does not

check the parity it receives. Use an RS-232 cable to connect the

external device to the scale, or construct one following the instruc-

tions below.

Connect a high quality, shielded cable with a DB9S (D-Subminiature 9 pin

female connector) using the following pinout:

1 2 3 4 5 PIN DESCRIPTION

• • • • • 2 TXD - scale transmits data

• • • • 3 RXD - scale receives data

6 7 8 9 5 GRD - signal ground

6 +5V @ 250mA* (optional)

Note: “Handshake” signals, such as “Clear To Send” (CTS), are not used. The

peripheral must have a minimum buffer (15 characters).

* An optional fuse is available to provide power for the Auto Count

200 bar code accessory or a decoded bar code scanning device

(wand, CCD, laser scanner) on pin 6.