small refactoring
small refactoring

KABA-CCEAC/node-ftdi,KABA-CCEAC/node-ftdi,thomaschaaf/node-ftdi,thomaschaaf/node-ftdi,KABA-CCEAC/node-ftdi,thomaschaaf/node-ftdi,thomaschaaf/node-ftdi,thomaschaaf/node-ftdi,KABA-CCEAC/node-ftdi,KABA-CCEAC/node-ftdi