xr16v2551im Exar Corporation, xr16v2551im Datasheet - Page 8
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xr16v2551im
Manufacturer Part Number
xr16v2551im
Description
High Performance Duart With 16-byte Fifo And Powersave Feature
Manufacturer
Exar Corporation
Datasheet
1.XR16V2551IM.pdf
(51 pages)
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
xr16v2551im-F
Manufacturer:
Exar Corporation
Quantity:
10 000
XR16V2551
HIGH PERFORMANCE DUART WITH 16-BYTE FIFO AND POWERSAVE FEATURE
The CPU interface is 8 data bits wide with 3 address lines and control signals to execute data bus read and
write transactions. The V2551 data interface supports the Intel compatible types of CPUs and it is compatible
to the industry standard 16C550 UART. No clock (oscillator nor external clock) is required to operate a data
bus transaction. Each bus cycle is asynchronous using CSA#/CSB#, IOR# and IOW# or CS#, R/W# and A3
inputs. Both UART channels share the same data bus for host operations. A typical data bus interconnection
for Intel and Motorola mode is shown in
The V2551 can accept up to 5V inputs even when operating at 3.3V or 2.5V. But note that if the V2551 is
operating at 2.5V, its V
transceiver that is operating at 5V.
F
2.0 FUNCTIONAL DESCRIPTIONS
2.1
2.2
IGURE
3. XR16V2551 T
CPU Interface
5-Volt Tolerant Inputs
U ART_RESET#
UAR T_C SA#
UAR T_C SB#
UAR T_R ESET
UAR T_IR Q #
U ART_INTA
U ART_INTB
UAR T_C S#
RXR D YA#
RXR D YB#
TXR DYA#
TXR DYB#
RXR D YA#
RXR D YB#
TXR DYA #
TXR DYB #
IO W #
R /W #
IO R #
A0
A1
A2
D 0
D 1
D 2
D 3
D 4
D 5
D 6
D 7
A0
A1
A2
A3
D 0
D 1
D 2
D 3
D 4
D 5
D 6
D 7
OH
YPICAL
may not be high enough to meet the requirements of the V
I
NTEL
/M
M otorola Data Bus Interconnections
Figure
Intel Data Bus Interconnections
OTOROLA
VCC
(no connect)
3.
D
VCC
ATA
8
B
TXRDYA#
R XRD YA#
TXRDYB#
R XRD YB#
US
IO R #
IO W #
C SA#
C SB#
INTA
INTB
RESET
TXRD YA#
R XRD YA#
TXRD YB#
R XRD YB#
D 0
D 1
D 2
D 3
D 4
D 5
D 6
D 7
C SB#
IO R #
IO W #
CSA#
IN TA
IN TB
A 0
A 1
A 2
R ESET#
D0
D1
D2
D3
D4
D5
D6
D7
A0
A1
A2
I
NTERCONNECTIONS
Channel A
Channel B
C hannel A
C hannel B
UAR T
UAR T
U ART
U ART
D TR B #
D SRB#
D TR A#
DSR A#
O P2A#
D TR B#
DSR B#
O P2B#
D SRA#
O P2A#
R TSB#
C TSB#
O P2B#
RTSA#
CTSA#
RTSB#
CTSB#
DTRA#
R TSA#
C TSA#
C DA#
C DB#
C D A#
CD B#
RIA#
RIB#
G N D
RIA#
G ND
TXB
RXB
RIB#
TXA
R XA
TXB
R XB
VCC
VC C
TXA
RXA
VC C
2.25 to 3.6 Volt VC C
(no connect)
(no connect)
(no connect)
(no connect)
Serial Interface of
Serial Interface of
Serial Interface of
Serial Interface of
RS-232, R S-422
RS-232, R S-422
R S-232, RS-422
R S-232, RS-422
IH
of a CPU or a serial
REV. 1.0.2