xr16v2552il32 Exar Corporation, xr16v2552il32 Datasheet - Page 9

• Manufacturer Part Number: xr16v2552il32
• Description: High Performance Duart With 16-byte Fifo
• Manufacturer: Exar Corporation

REV. 1.0.2
The INTA and INTB interrupt output changes according to the operating mode and enhanced features setup.
Table 3 and 4
through
The V2552 includes an on-chip oscillator (XTAL1 and XTAL2) to produce a clock for both UART sections in the
device. The CPU data bus does not require this clock for bus operation. The crystal oscillator provides a
system clock to the Baud Rate Generators (BRG) section found in each of the UART. XTAL1 is the input to the
oscillator or external clock buffer input with XTAL2 pin being the output. Please note that the input XTAL1 is not
5V tolerant and so the maximum at the pin should be VCC. For programming details, see
Programmable Baud Rate Generator with Fractional Divisor” on page
F
2.8
2.9
IGURE
INTA/B Pin
INTA/B Pin
INTA/B Pin
4. T
INTA and INTB Outputs
Crystal Oscillator or External Clock Input
22.
YPICAL
summarize the operating behavior for the transmitter and receiver. Also see
A
LOW = no data
HIGH = 1 byte
UTO
C
M
YES
RYSTAL CONNECTIONS
NO
ODE
RS485
(FIFO D
T
FCR B
ABLE
T
ABLE
LOW = a byte in THR
HIGH = THR empty
LOW = a byte in THR
HIGH = transmitter empty
IT
ISABLED
3: INTA
-0 = 0
4: INTA
)
(FIFO D
FCR B
AND
AND
22-47pF
XTAL1
INTB P
C1
IT
ISABLED
LOW = FIFO below trigger level
HIGH = FIFO above trigger level
INTB P
-0 = 0
INS
500K - 1M
)
R2
IN
9
HIGH PERFORMANCE DUART WITH 16-BYTE FIFO
22-47pF
XTAL2
O
O
C2
Y1
PERATION FOR
PERATION
1.8432 MHz
LOW = FIFO above trigger level
HIGH = FIFO below trigger level or FIFO empty
LOW = FIFO above trigger level
HIGH = FIFO below trigger level or transmitter empty
(Optional)
24 MHz
0-120
R1
to
F
OR
(FIFO E
FCR B
FCR B
T
RANSMITTER
R
ECEIVER
10.”
IT
IT
NABLED
-0 = 1
-0 = 1 (FIFO E
)
NABLED
XR16V2552
““Section 2.10,
Figures 17
)