Barcode USB scanner stream
A NodeJs transform stream to convert a barcode (from an USB scanner) into a string representation.
npm --save usb-barcode-transform
const fs = ;const Scanner = ;const stream = fs;stream;
Groupped Scanner Example
The scanner will send every single character as an ASCII character. The
stream estract only visible characters and exclude any escape sequence.
const fs = ;const barcode = ;const stream = fs;stream;
Group send a single event that represent the decoded value (1234567)
without any escape sequence or carriage return
The event struct in the linux kernel have this interface
'time' is the timestamp, it returns the time at which the event happened. Type is for example EV_REL for relative moment, EV_KEY for a keypress or release. More types are defined in include/uapi/linux/input-event-codes.h.
'code' is event code, for example REL_X or KEY_BACKSPACE, again a complete list is in include/uapi/linux/input-event-codes.h.
'value' is the value the event carries. Either a relative change for EV_REL, absolute new value for EV_ABS (joysticks ...), or 0 for EV_KEY for release, 1 for keypress and 2 for autorepeat.