Symbol Technologies DS 3408 - Manual (Page 278)

DS 3408 Product Reference Guide 15-46
Beeps
Select a beep sequence for each ADF rule.
Send Keystroke (Control Characters and Keyboard Characters)
Control Characters
Scan the “Send __” bar code for the keystroke to send
Beep Once
Beep Twice
Beep Three Times
Send Control 2
Send Control A
Send Control B