Barcodes stored by mobile devices can be used in commerce. In sending barcode data optically from a display backlight of a mobile communication device to a barcode scanner optical receiver, the transmitted data bit time needs to be compatible with the frequency range the barcode scanner is designed to receive. The disclosed methods and mobile devices can send barcode data optically at different frequencies from a modulated display backlight to different models/makes of laser barcode scanners that may be used at a point of sale (POS). The disclosed are methods and devices for processing the bit time mix choices make a determination of bit time mix choices based upon predetermined criteria. Location of the device is an example of predetermined criteria. A location may have a particular bit time mix signature that may be accessed, for example, in a look up table.