# Barcode Best Practices

### Important Information

* The barcode device is closed by default. To start communications with the barcode module, Barcode device open command needs to be sent first.
* To save battery power, power down the barcode module using command Barcode device close when using barcode module is done.
* The default scan trigger mode is LEVEL.
* By default, continuous scan mode is enabled. Single scan mode is enabled automatically when continuous scan mode is disabled. In single scan mode, scanner shuts off scan session after successful scan of barcode.
* All barcode parameters are restored to their default values when the restore defaults command is called.
* Barcode application expects one command at a time. Next command can’t be sent to Barcode application until Success/Failure response of previous command is received.
* Configuration remains persistent across application and device restart, instead of reverting back to default.
* It is recommended not to use the barcode functionality from the barcode library and T11 command simultaneously.

Functionality comparison and limitations/known issues are preserved from the original document (including differences between e355 and e280s and limitations such as module timeout in sleep mode, PIN entry interactions, etc.).


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