xr16m2550 Exar Corporation, xr16m2550 Datasheet - Page 46

• Manufacturer Part Number: xr16m2550
• Description: High Performance Low Voltage Duart With 16-byte Fifo
• Manufacturer: Exar Corporation

XR16M2550
HIGH PERFORMANCE LOW VOLTAGE DUART WITH 16-BYTE FIFO
GENERAL DESCRIPTION ................................................................................................ 1
PIN DESCRIPTIONS ........................................................................................................ 3
1.0 PRODUCT DESCRIPTION....................................................................................................................... 6
2.0 FUNCTIONAL DESCRIPTIONS............................................................................................................... 7
3.0 UART INTERNAL REGISTERS ............................................................................................................. 21
4.0 INTERNAL REGISTER DESCRIPTIONS............................................................................................... 23
A
F
ORDERING INFORMATION
EATURES
PPLICATIONS
2.1 CPU INTERFACE................................................................................................................................................. 7
2.2 DEVICE RESET ................................................................................................................................................... 7
2.3 DEVICE IDENTIFICATION AND REVISION........................................................................................................ 7
2.4 CHANNEL A AND B SELECTION....................................................................................................................... 7
2.5 CHANNEL A AND B INTERNAL REGISTERS ................................................................................................... 8
2.6 DMA MODE.......................................................................................................................................................... 8
2.7 INTA AND INTB OUTPUTS ................................................................................................................................. 9
2.8 CRYSTAL OSCILLATOR OR EXTERNAL CLOCK INPUT ................................................................................ 9
2.9 PROGRAMMABLE BAUD RATE GENERATOR WITH FRACTIONAL DIVISOR............................................ 10
2.10 TRANSMITTER ................................................................................................................................................ 12
2.11 RECEIVER ....................................................................................................................................................... 13
2.12 AUTO RTS (HARDWARE) FLOW CONTROL ................................................................................................ 15
2.13 AUTO RTS HYSTERESIS............................................................................................................................... 15
2.14 AUTO CTS FLOW CONTROL ........................................................................................................................ 15
2.15 AUTO XON/XOFF (SOFTWARE) FLOW CONTROL...................................................................................... 17
2.16 SPECIAL CHARACTER DETECT .................................................................................................................. 17
2.17 INFRARED MODE .......................................................................................................................................... 18
2.18 SLEEP MODE WITH AUTO WAKE-UP.......................................................................................................... 19
2.19 INTERNAL LOOPBACK ................................................................................................................................. 20
4.1 RECEIVE HOLDING REGISTER (RHR) - READ- ONLY .................................................................................. 23
4.2 TRANSMIT HOLDING REGISTER (THR) - WRITE-ONLY ............................................................................... 23
4.3 INTERRUPT ENABLE REGISTER (IER) - READ/WRITE................................................................................. 23
4.4 INTERRUPT STATUS REGISTER (ISR) - READ-ONLY .................................................................................. 25
F
F
F
T
T
T
T
F
F
T
F
F
F
F
T
F
T
F
F
T
T
IGURE
IGURE
IGURE
ABLE
ABLE
ABLE
ABLE
IGURE
IGURE
ABLE
IGURE
IGURE
IGURE
IGURE
ABLE
IGURE
ABLE
IGURE
IGURE
ABLE
ABLE
2.10.1 TRANSMIT HOLDING REGISTER (THR) - WRITE ONLY ......................................................................................... 12
2.10.2 TRANSMITTER OPERATION IN NON-FIFO MODE .................................................................................................. 12
2.10.3 TRANSMITTER OPERATION IN FIFO MODE ........................................................................................................... 12
2.11.1 RECEIVE HOLDING REGISTER (RHR) - READ-ONLY ............................................................................................ 13
4.3.1 IER VERSUS RECEIVE FIFO INTERRUPT MODE OPERATION ............................................................................... 23
4.3.2 IER VERSUS RECEIVE/TRANSMIT FIFO POLLED MODE OPERATION .................................................................. 24
1: C
2: TXRDY#
3: INTA
4: INTA
5: T
6: A
7: A
8: UART CHANNEL A AND B UART INTERNAL REGISTERS ....................................................................................... 21
9: INTERNAL REGISTERS DESCRIPTION. S
1. XR16M2550 B
2. P
3. XR16M2550 D
4. T
5. B
6. T
7. T
8. R
9. R
10. A
11. I
12. I
.................................................................................................................................................... 1
YPICAL DATA RATES WITH A
UTO
UTO
HANNEL
YPICAL OSCILLATOR CONNECTIONS
RANSMITTER
RANSMITTER
IN
AUD
ECEIVER
ECEIVER
NFRARED
NTERNAL
............................................................................................................................................... 1
UTO
O
AND
AND
RTS (H
X
UT
R
ON
RTS
ATE
AND
A
A
INTB P
INTB P
/X
O
O
SSIGNMENT
AND
L
OFF
T
G
PERATION IN NON
PERATION IN
OOP
ARDWARE
AND
RANSMIT
RXRDY# O
ENERATOR
O
O
................................................................................................................................ 2
LOCK
ATA
B S
PERATION IN NON
PERATION IN
(S
INS
IN
CTS F
B
OFTWARE
ACK IN
ELECT
O
B
O
D
US
PERATION
..................................................................................................................................................... 2
D
) F
IAGRAM
PERATION FOR
ATA
LOW
I
............................................................................................................................................... 11
NTERCONNECTIONS
FIFO
UTPUTS IN
LOW
C
............................................................................................................................................... 8
24 MH
) F
HANNEL
E
FIFO
C
-FIFO M
NCODING AND
C
........................................................................................................................................ 1
LOW
ONTROL
AND
TABLE OF CONTENTS
F
ONTROL
OR
-FIFO M
Z CRYSTAL OR EXTERNAL CLOCK AT
AND
................................................................................................................................. 9
C
A
FIFO
A
R
ONTROL
UTO
T
ODE
ECEIVER
AND
RANSMITTER
O
F
........................................................................................................................ 15
LOW
PERATION
ODE
RTS F
AND
.................................................................................................................... 14
B ................................................................................................................ 20
R
................................................................................................................... 7
HADED BITS ARE ENABLED WHEN
ECEIVE
C
.............................................................................................................. 12
............................................................................................................... 17
DMA M
ONTROL
............................................................................................................... 9
LOW
....................................................................................................... 16
........................................................................................................ 9
I
D
C
ODE
ATA
ONTROL
M
ODE
D
............................................................................................. 8
ECODING
..................................................................................... 13
M
ODE
16X S
.......................................................................... 18
......................................................................... 14
AMPLING
EFR B
IT
................................................... 11
-4=1 .......................................... 22
REV. 1.0.2