NO:
W90P710 Programming Guide
VERSION:
2.0
PAGE:
142
The above information is the exclusive intellectual property of Winbond Electronics and shall not be disclosed, distributed or reproduced without permission
from Winbond.
Table No.: 2005-W90P710-11-A
11 UART
11.1 Overview
Universal Asynchronous Receiver/Transmitter (UART) performs a serial-to-parallel conversion for
the input data. The character bits received from UART receive pin
(SIN)
are shifted to Receive FIFO
one after by one. The driver reads the receive FIFO to get the input character. The UART also
performs a parallel-to-serial conversion for output data. The driver writes the output characters to the
transmitter FIFO. Then the character bits are shifted to UART transmit pin
(SOUT)
in sequence.
The UART provides control/status registers and an interrupt for device driver to control the
transmitting operation, receiving operation and error handling. There are five types of interrupts
including
line status interrupt
,
transmitter FIFO empty interrupt
,
receiver threshold level reaching
interrupt
,
time out interrupt
, and
MODEM status interrupt
. The provided status information includes
the type and condition of the transfer operations being performed by the UART, as well as any found
error conditions (parity, overrun, framing, or break interrupt).
W90P710’s Asynchronous serial communication block include 4
UART
blocks and accessary
logic. The feature of each UART could be found in datasheet.
11.2 Registers
R
: read only,
W
: write only,
R/W
: both read and write,
C
: Only value 0 can be written
Register
Address
R/W
Description and Condition
Reset value
UART0
UART0_RBR
0xFFF8.0000
R
Receive Buffer Register (DLAB = 0)
Undefined
UART0_THR
0xFFF8.0000
W
Transmit Holding Register (DLAB = 0)
Undefined
UART0_IER
0xFFF8.0004
R/W Interrupt Enable Register (DLAB = 0)
0x0000.0000