22–1 
IS4823 and IS4825 Scan Engines 
Operating Modes 
Activation Modes 
 
*  Activate Scanning with the External Trigger –  
An external I/O pin is used to enable the scanning 
cycle. A High-to-Low transition on the I/O signal is 
used to activate scanning. The signal must be 
deactivated (HIGH) and re-activated for 
subsequent scanning cycles. The scanning cycle 
is terminated based on the default period of time  
(2 seconds), a variable period of time, when the 
I/O signal is deactivated (Low-to-High), or when a 
bar code is scanned and transmitted. 
 
  Activate Scanning on Receipt of the <DC2> 
Character – A received <DC2> character initiates 
the scanning cycle. The scanning cycle is 
terminated based on the default period of time  
(2 seconds), variable laser timeout selected, or 
when a bar code is scanned and transmitted.  
  
  Activate Scanning Using D/E – A received ‘E’ 
character initiates the scanning cycle. The 
scanning cycle is terminated based on the default 
period of time (2 seconds), variable laser timeout 
selected, or receipt of a ‘D’ or when a bar code is 
scanned and transmitted. 
 
  Activate Scanning with Address – A 
configurable address character is used to initiate 
scanning. T
he scanning cycle is terminated based 
on the default period of time (2 seconds), variable 
laser timeout selected, or when a bar code is 
scanned and transmitted. 
 
~ Address Value – Use this bar code with a code 
byte sequence (on page 16–1) that represents 
the desired character to be used to initiate 
scanning. An ASCII reference table is available 
on page 16–3.