Zebra DS8178 Product Reference Guide

SSI Interface 8 - 3
SSI Transactions
General Data Transactions
ACK/NAK Handshaking
If you enable ACK/NAK handshaking, all packeted messages must have a CMD_ACK or CMD_NAK response,
unless the command description states otherwise. This parameter is enabled by default. Zebra recommends
leaving this handshaking enabled to provide feedback to the host. Raw decode data and WAKEUP do not use
ACK/NAK handshaking since they are not packeted data.
Following is an example of a problem which can occur if you disable ACK/NAK handshaking:
• The host sends a PARAM_SEND message to the digital scanner to change the baud rate from 9600 to
19200.
• The digital scanner cannot interpret the message.
• The digital scanner does not implement the change the host requested.
• The host assumes that the parameter change occurred and acts accordingly.
• Communication is lost because the change did not occur on both sides.
If you enable ACK/NAK handshaking, the following occurs:
• The host sends a PARAM_SEND message.
• The digital scanner cannot interpret the message.
• The digital scanner CMD_NAKs the message.
• The host resends the message.
• The digital scanner receives the message successfully, responds with CMD_ACK, and implements
parameter changes.

Zebra DS8178 Specifications

General

Product color	Black
Housing material	-
International Protection (IP) code	IP42
Type	Handheld bar code reader
Wavelength	617 nm
Sensor type	Photo diode
Scanner type	1D/2D
Tilt reading angle	0 - 360 °
Pitch reading angle	0 - 60 °
Optical sensor resolution	1280 pixels
Storage temperature (T-T)	-40 - 70 °C
Operating temperature (T-T)	0 - 50 °C
Operating relative humidity (H-H)	5 - 95 %
PC connection	RS-232/USB
Wireless range	100 m
Bluetooth version	4.0
Standard interfaces	USB, RS-232, Bluetooth
Connectivity technology	Wired & Wireless
Battery life	83 h
Battery capacity	2500 mAh
Power source type	Battery

Weight and Dimensions

Depth	107 mm
Width	66 mm
Height	168 mm
Weight	235.3 g