xr16v2650im Exar Corporation, xr16v2650im Datasheet - Page 9

• Manufacturer Part Number: xr16v2650im
• Description: High Performance Duart With 32-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 V2650 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
INTA/B Pin LOW = a byte in THR
INTA/B Pin LOW = a byte in THR
INTA/B Pin LOW = no data
IGURE
4. T
INTA and INTB Outputs
Crystal Oscillator or External Clock Input
22.
YPICAL
HIGH = THR empty
HIGH = transmitter empty
HIGH = 1 byte
summarize the operating behavior for the transmitter and receiver. Also see
C
RYSTAL CONNECTIONS
T
ABLE
T
ABLE
(FIFO D
(FIFO D
FCR B
FCR B
3: INTA
4: INTA
IT
ISABLED
IT
ISABLED
-0 = 0
-0 = 0
AND
AND
)
)
INTB P
22-47pF
XTAL1
INTB P
C1
INS
INS
500K - 1M
9
HIGH PERFORMANCE DUART WITH 32-BYTE FIFO
O
R2
22-47pF
O
PERATION FOR
XTAL2
PERATION
C2
Y1
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
LOW = FIFO below trigger level
HIGH = FIFO above trigger level
1.8432 MHz
(Optional)
24 MHz
0-120
R1
to
F
OR
FCR B
T
RANSMITTER
R
10.”
ECEIVER
IT
(FIFO E
FCR B
-0 = 1 (FIFO E
IT
NABLED
-0 = 1
NABLED
)
XR16V2650
““Section 2.10,
Figures 17
)