21-05-2013, 12:36 PM
Basic communications ports in any PC
Basic communications.ppt (Size: 148.5 KB / Downloads: 16)
SERIAL PORTS
Classic serial port was a carryover from a previous generation of technology
Low speed was a sad match for the quick pulse of the PC
SERIAL PORTS characteristics
No synchronization or clocking signal is present; so characters can be sent with any arbitrary time spacing.
A single 0 bit, called a the start bit, precedes each character to tell the receiving system that the next eight bits constitute a byte of data.
One or two stop bits follow the character to signal that the character has been sent.