xr16m752im48 Exar Corporation, xr16m752im48 Datasheet - Page 8

• Manufacturer Part Number: xr16m752im48
• Description: Xr68m752 -high Performance Duart With 64-byte Fifo
• Manufacturer: Exar Corporation

XR16M752/XR68M752
HIGH PERFORMANCE DUART WITH 64-BYTE FIFO
The CPU interface is 8 data bits wide with 3 address lines and control signals to execute data bus read and
write transactions. The XR16M752 data interface supports the Intel compatible types of CPUs while the
XR68M752 supports both the Intel and Motorola compatible data interfaces. No clock (oscillator nor external
clock) is required to operate a data bus transaction. Each bus cycle is asynchronous using CS#, IOR# and
IOW# signals. Both UART channels share the same data bus for host operations. The data bus
interconnections are shown in
F
2.0 FUNCTIONAL DESCRIPTIONS
2.1
IGURE
3. XR16M752/XR68M752 D
CPU Interface
UART_RESET#
UART_CSA#
UART_CSB#
UART_RESET
UART_IRQ#
UART_INTA
UART_INTB
UART_CS#
RXRDYA#
RXRDYB#
TXRDYA#
TXRDYB#
RXRDYA#
RXRDYB#
TXRDYA#
TXRDYB#
IO W #
R/W #
IO R#
A0
A1
A2
D0
D1
D2
D3
D4
D5
D6
D7
A0
A1
A2
A3
D0
D1
D2
D3
D4
D5
D6
D7
Figure
ATA
3.
M otorola Data Bus Interconnections
Intel Data Bus Interconnections
B
VCC
US
(no connect)
I
NTERCONNECTIONS
VCC
8
TXRDYA#
RXRDYA#
TXRDYB#
RXRDYB#
IOR #
IOW #
CSA#
CSB#
INTA
INTB
RESET
TXRDYA#
RXRDYA#
TXRDYB#
RXRDYB#
D0
D1
D2
D3
D4
D5
D6
D7
CSA#
INTA
INTB
CSB#
IOR #
IOW #
RESET #
D0
D1
D2
D3
D4
D5
D6
D7
A0
A1
A2
A0
A1
A2
Channel A
Channel B
Channel A
Channel B
UART
UART
UART
UART
DTRB#
DSRB#
DSRA#
OP2A#
DTRB#
DSRB#
OP2B#
OP2A#
DTRA#
RTSA#
CTSA#
RTSB#
CTSB#
DTRA#
RTSA#
CTSA#
DSRA#
RTSB#
CTSB#
OP2B#
CDA#
CDA#
CDB#
CDB#
RIB#
GND
RIA#
G ND
RIA#
TXB
RIB#
TXA
RXA
TXB
RXB
RXB
VCC
TXA
RXA
VCC
VCC
2.25 to 3.6 Volt VCC
(no connect)
(no connect)
(no connect)
(no connect)
Serial Interface of
Serial Interface of
Serial Interface of
Serial Interface of
RS-232, RS-422
RS-232, RS-422
RS-232, RS-422
RS-232, RS-422
or RS-485
or RS-485
or RS-485
or RS-485
REV. 1.0.2