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Rainbow Electronics W90N745CDG User Manual

Page 272

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W90N745CD/W90N745CDG

Publication Release Date: September 22, 2006

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267

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Revision

A2

Table 6.10.6 Interrupt Control Functions

IIR [3:0]

PRIORITY

INTERRUPT

TYPE

INTERRUPT SOURCE

INTERRUPT RESET

CONTROL

-

-

-

1 --

None

None

--

0110 Highest

Receiver Line

Status (Irpt_RLS)

Overrun error, parity error,
framing error, or break
interrupt

Reading the LSR

0100 Second

Received Data

Available

(Irpt_RDA)

Receiver FIFO threshold
level is reached

Receiver FIFO drops
below the threshold
level

1100 Second

Receiver FIFO

Time-out

(Irpt_TOUT)

Receiver FIFO is non-empty
and no activities are
occurred in the receiver
FIFO during the TOR
defined time duration

Reading the RBR

0010 Third

Transmitter

Holing Register

Empty

(Irpt_THRE)

Transmitter holding register
empty

Reading the IIR (if
source of interrupt is
Irpt_THRE) or writing
into the THR

0000 Fourth

MODEM Status

(Irpt_MOS)

The CTS, DSR, or DCD bits
are changing state or the RI
bit is changing from high to
low.

Reading the MSR
(optional)

Note: These definitions of bit 7, bit 6, bit 5, and bit 4 are different from the 16550

UART FIFO Control Register (UART_FCR)

REGISTER OFFSET R/W

DESCRIPTION

RESET

VALUE

UART_FCR

0x08

W

FIFO Control Register

Undefined

31

30

29

28

27

26

25

24

Reserved

23

22

21

20

19

18

17

16

Reserved

15

14

13

12

11

10

9

8

Reserved

7

6

5

4

3

2

1

0

RFITL

RESERVED

DMS

TFR

RFR

FME