XR16C850CM EXAR [Exar Corporation], XR16C850CM Datasheet - Page 9

• Manufacturer Part Number: XR16C850CM
• Description: 2.97V TO 5.5V UART WITH 128-BYTE FIFO
• Manufacturer: EXAR [Exar Corporation]

xr
REV. 2.3.1
The host interface is 8 data bits wide with 3 address lines and control signals to execute bus read and write
transactions. The 850 supports 2 types of host interfaces: Intel and PC mode. The Intel bus interface is
selected by connecting SEL to logic 1. When the SEL pin is set to a logic 1, the 850 interface is the same as
industry standard 16C550. The Intel bus interconnections are shown in
selected when SEL is connected to logic 0. The PC mode interconnections are shown in
.
2.0 FUNCTIONAL DESCRIPTIONS
2.1
Host Data Bus Interface
F
F
IGURE
IGURE
RESET
A14
A15
AEN#
RESET
A2
IOR#
IRQ4
IOW
CS#
INT
D0
D1
D2
D3
D4
D5
D6
D7
A0
A1
A2
A4
A7
IOW#
IRQn
IRQ3
D0
D1
D2
D3
D4
D5
D6
D7
A0
IOR
A3
A5
A6
A1
3. XR16C850 I
4. XR16C850 PC M
NTEL
ODE
B
US
I
NTERCONNECTIONS
I
NTERCONNECTIONS
9
GND
GND
VCC
2.97V TO 5.5V UART WITH 128-BYTE FIFO
IOW #
IOR#
CS2#
RESET
INT
A1
AEN
IRQA
IRQB
IRQC
RESET
D0
D1
D2
D3
D4
D5
D6
D7
A0
A1
A2
D0
D1
D2
D3
D4
D5
D6
D7
A0
A2
IOR#
IOW#
A3
A4
A5
A6
A7
A8
A9
S3
S2
S1
BAUDOUT#
Figure
RCLK
DSR#
OP2#
DSR#
DTR#
RTS#
CTS#
OP1#
DTR#
RTS#
CTS#
OP1#
GND
VCC
CD#
GND
VCC
CD#
IOW
RX
RX
TX
RI#
CS0
CS1
SEL
TX
RI#
IOR
AS#
SEL
3. The special PC mode is
VCC
VCC
Figure
4.
XR16C850