ST16C2550CQ48 EXAR [Exar Corporation], ST16C2550CQ48 Datasheet - Page 4

• Manufacturer Part Number: ST16C2550CQ48
• Description: 2.97V TO 5.5V DUART WITH 16-BYTE FIFO
• Manufacturer: EXAR [Exar Corporation]

ST16C2550
2.97V TO 5.5V DUART WITH 16-BYTE FIFO
PIN DESCRIPTIONS
Pin Description
DATA BUS INTERFACE
RXRDYA#
TXRDYA#
IOW#
CSA#
CSB#
N
IOR#
INTB
INTA
A2
A1
A0
D7
D6
D5
D4
D3
D2
D1
D0
AME
40-PDIP
P
26
27
28
21
18
14
15
30
29
IN
8
7
6
5
4
3
2
1
-
-
#
44-PLCC
P
29
30
31
24
20
16
17
33
32
34
IN
9
8
7
6
5
4
3
2
1
#
48-TQFP
P
26
27
28
48
47
46
45
44
19
15
10
11
30
29
43
31
IN
3
2
1
#
T
YPE
IO
O
O
O
O
I
I
I
I
I
4
Address data lines [2:0]. These 3 address lines select one
of the internal registers in UART channel A/B during a
data bus transaction.
Data bus lines [7:0] (bidirectional).
Input/Output Read Strobe (active low). The falling edge
instigates an internal read cycle and retrieves the data
byte from an internal register pointed to by the address
lines [A2:A0]. The data byte is placed on the data bus to
allow the host processor to read it on the rising edge.
Input/Output Write Strobe (active low). The falling edge
instigates an internal write cycle and the rising edge
transfers the data byte on the data bus to an internal reg-
ister pointed by the address lines.
UART channel A select (active low) to enable UART
channel A in the device for data bus operation.
UART channel B select (active low) to enable UART
channel B in the device for data bus operation.
UART channel A Interrupt output. The output state is
defined by the user and through the software setting of
MCR[3]. INTA is set to the active mode and OP2A# out-
put to a logic 0 when MCR[3] is set to a logic 1. INTA is
set to the three state mode and OP2A# to a logic 1 when
MCR[3] is set to a logic 0 (default). See MCR[3].
UART channel B Interrupt output. The output state is
defined by the user and through the software setting of
MCR[3]. INTB is set to the active mode and OP2B# out-
put to a logic 0 when MCR[3] is set to a logic 1. INTB is
set to the three state mode and OP2B# to a logic 1 when
MCR[3] is set to a logic 0 (default). See MCR[3].
UART channel A Transmitter Ready (active low). The out-
put provides the TX FIFO/THR status for transmit channel
A. See
UART channel A Receiver Ready (active low). This out-
put provides the RX FIFO/RHR status for receive channel
A. See
Table
Table
2. If it is not used, leave it unconnected.
2. If it is not used, leave it unconnected.
D
ESCRIPTION
xr
REV. 4.4.0