XR16L788
HIGH PERFORMANCE 2.97V TO 5.5V OCTAL UART
JULY 2008
REV. 1.2.3
GENERAL DESCRIPTION
The XR16L7881 (788), is a 2.97V to 5.5V with 5V
tolerant inputs octal Universal Asynchronous
Receiver and Transmitter (UART). The highly
integrated device is designed for high bandwidth
requirement in communication systems. The global
interrupt source register provides a complete interrupt
status indication for all 8 channels to speed up
interrupt parsing. Each UART has its own 16C550
compatible set of configuration registers, TX and RX
FIFOs of 64 bytes, fully programmable transmit and
receive FIFO trigger levels, TX and RX FIFO level
counters, automatic RTS/CTS or DTR/DSR hardware
flow control with programmable hysteresis, autoamtic
software (Xon/Xoff) flow control, RS-485 half-duplex
direction control with programmable turn-around
delay, Intel or Motorola bus interface and sleep mode
with a wake-up indicator.
N
OTE
:
Covered by US patents #5,649,122 and #5,949,787
FEATURES
•
2.97V to 5.5V with 5V Tolerant Inputs Operation
•
Single Interrupt Output for all 8 UARTs
•
Global Interrupt Source for all 8 UARTs
•
5G “Flat” UART Registers for Configurations
•
Simultaneous UART Channels Initialization
•
Auto RS485 Half-duplex Control with Program-
mable Turn-around Delay
APPLICATIONS
•
Remote Access Servers
•
Ethernet Network to Serial Ports
•
Network Management
•
Factory Automation and Process Control
•
Point-of-Sale Systems
•
Multi-port RS-232/RS-422/RS-485 Cards
F
IGURE
1. B
LOCK
D
IAGRAM
•
A General Purpose 16-bit Timer/Counter
•
Sleep Mode with Wake-up Indication
•
Highly Integrated Device for Space Saving
•
First eight registers are 16C550 compatible
•
64-byte Transmit and Receive FIFOs
•
Transmit and Receive FIFO Level Counters
•
Programmable TX and RX FIFO Trigger Levels
•
Automatic RTS/CTS or DTR/DSR Flow Control
•
Selectable Hardware Flow Control Hysteresis
•
Automatic Xon/Xoff Software Flow Control with
Status Indicator
•
Infrared (IrDA 1.0) Data Encoder/Decoder
•
Programmable Data Rate with Prescaler
•
Up to 6.25 Mbps Serial Data Rate at 5V
•
100-pin QFP Package (14x20x3 mm)
UART Channel 0
UART
Regs
BRG
64 Byte TX FIFO
TX & RX
IR
ENDEC
TX0, RX0, DTR0#,
DSR0#, RTS0#,
CTS0#, CD0#, RI0#
RST#
A7:A0
D7:D0
IOR#
IOW#
CS#
INT#
16/68#
Data Bus
Interface
Device
Configuration
Registers
64 Byte RX FIFO
UART Channel 1
UART Channel 2
UART Channel 3
UART Channel 4
UART Channel 5
UART Channel 6
16-bit
Timer/Counter
UART Channel 7
TX7, RX7, DTR7#,
DSR7#, RTS7#,
CTS7#, CD7#, RI7#
XTAL1
XTAL2
TMRCK
Crystal Osc/Buffer
Exar
Corporation 48720 Kato Road, Fremont CA, 94538
•
(510) 668-7000
•
FAX (510) 668-7017
•
www.exar.com
XR16L788
HIGH PERFORMANCE 2.97V TO 5.5V OCTAL UART
REV. 1.2.3
F
IGURE
2. P
IN
O
UT OF THE
D
EVICE
TX2
DTR2#
RTS2#
RI2#
CD2#
DSR2#
CTS2#
RX2
TX3
DTR3#
RTS3#
RI3#
CD3#
DSR3#
CTS3#
RX3
TX4
DTR4#
RTS4#
RI4#
CD4#
DSR4#
CTS4#
RX4
TX5
DTR5#
RTS5#
RI5#
CD5#
DSR5#
80 79 78 77 76 75 74 73 72 71 70 69 68 67 66 65 64 63 62 61 60 59 58 57 56 55 54 53 52 51
81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100
XTAL2
XTAL1
GND
VCC
TX1
DTR1#
RTS1#
RI1#
CD1#
DSR1#
CTS1#
RX1
TX0
DTR0#
RTS0#
RI0#
CD0#
DSR0#
CTS0#
RX0
31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
CTS5#
RX5
VCC
GND
TX6
DTR6#
RTS6#
RI6#
CD6#
DSR6#
CTS6#
RX6
TX7
DTR7#
RTS7#
RI7#
CD7#
DSR7#
CTS7#
RX7
XR16L788
100-QFP
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
ORDERING INFORMATION
P
ART
N
UMBER
XR16L788CQ
XR16L788IQ
P
ACKAGE
100-Lead QFP
100-Lead QFP
O
PERATING
T
EMPERATURE
R
ANGE
0°C to +70°C
-40°C to +85°C
D
EVICE
S
TATUS
Active
Active
RST#
16/68#
VCC
GND
D7
D6
D5
D4
D3
D2
D1
D0
IOW#
TMRCK
ENIR
INT#
VCC
GND
IOR#
A7
A6
A5
A4
A3
A2
A1
A0
VCC
GND
CS#
2
XR16L788
REV. 1.2.3
HIGH PERFORMANCE 2.97V TO 5.5V OCTAL UART
PIN DESCRIPTIONS
N
AME
P
IN
#
T
YPE
D
ESCRIPTION
DATA BUS INTERFACE
A7:A0
20-27
I
Address data lines [7:0]. A0:A3 selects individual UART’s 16 configuration
registers, A4:A6 selects UART channel 0 to7, and A7 selects the global device
configuration registers.
Data bus lines (7:0] (bidirectional).
When 16/68# pin is HIGH, it selects Intel bus interface and this input is read
strobe (active low). The falling edge instigates an internal read cycle and
retrieves the data byte from an internal register pointed by the address lines
[A7:A0], places it on the data bus to allow the host processor to read it on the
leading edge.
When 16/68# pin is LOW, it selects Motorola bus interface and this input
should be connected to VCC.
When 16/68# pin is HIGH, it selects Intel bus interface and this input becomes
write strobe (active low). The falling edge instigates the internal write cycle
and the leading edge transfers the data byte on the data bus to an internal
register pointed by the address lines.
When 16/68# pin is LOW, it selects Motorola bus interface and this input
becomes read (HIGH) and write (LOW) signal (R/W#).
When 16/68# pin is HIGH, this input is chip select (active low) to enable the
XR16L788 device.
When 16/68# pin is LOW, this input becomes the read and write strobe (active
low) for the Motorola bus interface.
Global interrupt output from XR16L788 (open drain, active low). This output
requires an external pull-up resistor (47K-100K ohms) to operate properly. It
may be shared with other devices in the system to form a single interrupt line
to the host processor and have the software driver polls each device for the
interrupt status.
D7:D0
IOR#
5-12
19
IO
I
IOW#
13
I
CS#
30
I
INT#
16
OD
MODEM OR SERIAL I/O INTERFACE
TX0
RX0
93
100
O
I
UART channel 0 Transmit Data or infrared transmit data.
UART channel 0 Receive Data or infrared receive data. Normal RXD input
idles HIGH. The infrared pulses can be inverted internally prior the decoder by
FCTR[4].
UART channel 0 Request to Send or general purpose output (active low). This
port may be used for one of two functions:
1) auto hardware flow control, see EFR bit-6, MCR bits-1 & 2, FCTR bits 0-3
and IER bit-6
2) RS485 half-duplex direction control, see FCTR bit-5, MCR bit-2 and MSR
bits 4-7.
UART channel 0 Clear to Send or general purpose input (active low). It can be
used for auto hardware flow control, see EFR bit-7, MCR bit-2 and IER bit-7.
UART channel 0 Data Terminal Ready or general purpose output (active low).
This port may be used one of two functions.
1) auto hardware flow control, see EFR bit-6, FCTR bits-0 to 3, MCR bits-0 &
2, and IER bit-6
2) RS485 half-duplex direction control, see FCTR bit-5, MCR bit-2 and MSR
bit 4-7.
UART channel 0 Data Set Ready or general purpose input (active low). It can
be used for auto hardware flow control, see EFR bit-7, MCR bit-2 and IER bit-
7.
RTS0#
95
O
CTS0#
DTR0#
99
94
I
O
DSR0#
98
I
3
XR16L788
HIGH PERFORMANCE 2.97V TO 5.5V OCTAL UART
N
AME
CD0#
RI0#
TX1
RX1
P
IN
#
97
96
85
92
T
YPE
I
I
O
I
D
ESCRIPTION
UART channel 0 Carrier Detect or general purpose input (active low).
UART channel 0 Ring Indicator or general purpose input (active low).
UART channel 1 Transmit Data or infrared transmit data.
UART channel 1 Receive Data or infrared receive data. Normal RXD input
idles HIGH. The infrared pulses can be inverted internally prior the decoder by
FCTR[4].
UART channel 1 Request to Send or general purpose output (active low). See
description of RTS0# pin.
UART channel 1 Clear to Send or general purpose input (active low). See
description of CTS0# pin.
UART channel 1 Data Terminal Ready or general purpose output (active low).
See description of DTR0# pin.
UART channel 1 Data Set Ready or general purpose input (active low). See
description of DSR0# pin.
UART channel 1 Carrier Detect or general purpose input (active low).
UART channel 1 Ring Indicator or general purpose input (active low).
UART channel 2 Transmit Data or infrared transmit data.
UART channel 2 Receive Data or infrared receive data. Normal RXD input
idles HIGH. The infrared pulses can be inverted internally prior the decoder by
FCTR[4].
UART channel 2 Request to Send or general purpose output (active low). See
description of RTS0# pin.
UART channel 2 Clear to Send or general purpose input (active low). See
description of CTS0# pin.
UART channel 2 Data Terminal Ready or general purpose output (active low).
See description of DTR0# pin.
UART channel 2 Data Set Ready or general purpose input (active low). See
description of DSR0# pin.
UART channel 2 Carrier Detect or general purpose input (active low).
UART channel 2 Ring Indicator or general purpose input (active low).
UART channel 3 Transmit Data or infrared transmit data.
UART channel 3 Receive Data or infrared receive data. Normal RXD input
idles HIGH. The infrared pulses can be inverted internally prior the decoder by
FCTR[4].
UART channel 3 Request to Send or general purpose output (active low). See
description of RTS0# pin.
UART channel 3 Clear to Send or general purpose input (active low). See
description of CTS0# pin.
UART channel 3 Data Terminal Ready or general purpose output (active low).
See description of DTR0# pin.
UART channel 3 Data Set Ready or general purpose input (active low). See
description of DSR0# pin.
UART channel 3 Carrier Detect or general purpose input (active low).
UART channel 3 Ring Indicator or general purpose input (active low).
REV. 1.2.3
RTS1#
CTS1#
DTR1#
DSR1#
CD1#
RI1#
TX2
RX2
87
91
86
90
89
88
80
73
O
I
O
I
I
I
O
I
RTS2#
CTS2#
DTR2#
DSR2#
CD2#
RI2#
TX3
RX3
78
74
79
75
76
77
72
65
O
I
O
I
I
I
O
I
RTS3#
CTS3#
DTR3#
DSR3#
CD3#
RI3#
70
66
71
67
68
69
O
I
O
I
I
I
4
XR16L788
REV. 1.2.3
HIGH PERFORMANCE 2.97V TO 5.5V OCTAL UART
P
IN
#
64
57
T
YPE
O
I
D
ESCRIPTION
UART channel 4 Transmit Data or infrared transmit data.
UART channel 4 Receive Data or infrared receive data. Normal RXD input
idles HIGH. The infrared pulses can be inverted internally prior the decoder by
FCTR[4].
UART channel 4 Request to Send or general purpose output (active low). See
description of RTS0# pin.
UART channel 4 Clear to Send or general purpose input (active low). See
description of CTS0# pin.
UART channel 4 Data Terminal Ready or general purpose output (active low).
See description of DTR0# pin.
UART channel 4 Data Set Ready or general purpose input (active low). See
description of DSR0# pin.
UART channel 4 Carrier Detect or general purpose input (active low).
UART channel 4 Ring Indicator or general purpose input (active low).
UART channel 5 Transmit Data or infrared transmit data.
UART channel 5 Receive Data or infrared receive data. Normal RXD input
idles HIGH. The infrared pulses can be inverted internally prior the decoder by
FCTR[4].
UART channel 5 Request to Send or general purpose output (active low). See
description of RTS0# pin.
UART channel 5 Clear to Send or general purpose input (active low). See
description of CTS0# pin.
UART channel 5 Data Terminal Ready or general purpose output (active low).
See description of DTR0# pin.
UART channel 5 Data Set Ready or general purpose input (active low). See
description of DSR0# pin.
UART channel 5 Carrier Detect or general purpose input (active low).
UART channel 5 Ring Indicator or general purpose input (active low).
UART channel 6 Transmit Data or infrared transmit data.
UART channel 6 Receive Data or infrared receive data. Normal RXD input
idles HIGH. The infrared pulses can be inverted internally prior the decoder by
FCTR[4].
UART channel 6 Request to Send or general purpose output (active low). See
description of RTS0# pin.
UART channel 6 Clear to Send or general purpose input (active low). See
description of CTS0# pin.
UART channel 6 Data Terminal Ready or general purpose output (active low).
See description of DTR0# pin.
UART channel 6 Data Set Ready or general purpose input (active low). See
description of DSR0# pin.
UART channel 6 Carrier Detect or general purpose input (active low).
UART channel 6 Ring Indicator or general purpose input (active low).
UART channel 7 Transmit Data or infrared transmit data.
N
AME
TX4
RX4
RTS4#
CTS4#
DTR4#
DSR4#
CD4#
RI4#
TX5
RX5
62
58
63
59
60
61
56
49
O
I
O
I
I
I
O
I
RTS5#
CTS5#
DTR5#
DSR5#
CD5#
RI5#
TX6
RX6
54
50
55
51
52
53
46
39
O
I
O
I
I
I
O
I
RTS6#
CTS6#
DTR6#
DSR6#
CD6#
RI6#
TX7
44
40
45
41
42
43
38
O
I
O
I
I
I
O
5