W83877ATF Datasheet, PDF (43/191 Pages) Winbond – enhanced version from Winbonds most popular I/O chip W83877F

W83877ATF
3.0 UART PORT
3.1 Universal Asynchronous Receiver/Transmitter (UART A, UART B)
The UARTs are used to convert parallel data into serial format on the transmit side, and convert serial
data to parallel format on the receiver side. The serial format, in order of transmission and reception,
is a start bit, followed by five to eight data bits, a parity bit (if programmed) and one, one and a half
(five-bit format only) or two stop bits. The UARTs are capable of handling divisors of 1 to 65535 and
producing a 16x clock for driving the internal transmitter logic. Provisions are also included to use this
16x clock to drive the receiver logic. The UARTs also support the MIDI data rate. Furthermore, the
UARTs also include complete modem control capability, and a processor interrupt system that may
be software trailed to the computing time required to handle the communication link. The UARTs
have a FIFO mode to reduce the number of interrupts presented to the CPU. In each UART, there are
16-byte FIFOs for both receive and transmit mode.
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Publication Release Date: April 1998
Version 0.51