Serial port requiring programs to refer to them by hardware address. Unix-like operating systems usually label the serial port devices /dev/tty*. "TTY" is a common trademark-free abbreviation for "teletype", a device commonly attached to early computers' serial ports, and * represents a string identifying the specific port; the syntax of that string depends on the operating system and the device. On Linux, 8250/16550 UART hardware serial ports are named /dev/ttyS*, USB adapters appear as /dev/ttyUSB* and various types of virtual serial ports do not necessarily have names starting with tty. The DOS and Windows environments refer to serial ports as COM ports:
Parallel and counter parallel by moving from the major dominant chord to the minor counter parallel: In four-part harmony, the Tcp usually has a doubled third to avoid consecutive fifths or octaves. This further emphasises its coherency with the tonic, since the third of the minor key counter parallel is the same as the tonic root which thus is doubled. Parallel and counter parallel In music, a parallel chord (relative chord, German: "Parallelklang") is an auxiliary chord derived from one of the primary triads and sharing its function: subdominant parallel, dominant parallel, and tonic parallel. The term is derived from German theory and the