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:
IPAQ (desktop computer) to the RAM limit of the Intel 815 series chipset, the BIOS in the iPAQ prevents the system from booting if there is more than 512 MB installed, instructing the user to decrease the amount of RAM in the system to no more than 512 MB. The first version came in two different models, "Legacy free" which had no parallel, serial, or PS/2 ports and instead 3 additional USB ports on the back; and the traditional one which included the parallel, serial, and PS/2 ports but only had USB ports on the front. The second version had different styling and