User manual

Serial Commands

Chapter 9

9–4

When the scanner is programmed for standby power

operation (@B), the first character of the command is

used to wake-up the scanner; it will not be recognized

by the scanner’s CPU. When there is any possibility

that the scanner is in standby mode, an extra space

code should be transmitted before STX to ensure the

scanner is awake before sending commands to it.

If you are not operating the scanner in standby mode,

the space has no effect on commands (space prefixed

commands are properly decoded).

Having sent the space code to wake-up the scanner, a

150 to 200 millisecond pause must be observed to

allow the scanner’s CPU to complete its initialization

tasks, during which time it is unable to accept serial

commands before issuing the programming

command. Failure to observe this delay causes the

scanner to ignore the incoming command.

All commands which affect serial communication are

acted upon immediately. When changing communi-

cation parameters (such as baud rate, word length,

parity), the scanner will send the ACK code, using

the newly implemented communication parameters.

There should be a delay after the host sends a

communication parameter setup command. This

delay allows the host computer to modify its internal

parameters and correctly receive the ACK code from

the scanner. This is due to the internal, one second

delay required for the scanner to update its internal

EEPROM.

ower Standb

and Serial

Commands

unication

Parameter

Changes