XR16C864IQ-F Exar Corporation, XR16C864IQ-F Datasheet - Page 18
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XR16C864IQ-F
Manufacturer Part Number
XR16C864IQ-F
Description
IC UART FIFO 128B QUAD 100QFP
Manufacturer
Exar Corporation
Type
Quad UART with 128-byte FIFOsr
Datasheet
1.XR16C864IQ-F.pdf
(51 pages)
Specifications of XR16C864IQ-F
Number Of Channels
4, QUART
Package / Case
100-BQFP
Features
*
Fifo's
128 Byte
Protocol
RS232, RS485
Voltage - Supply
2.97 V ~ 5.5 V
With Auto Flow Control
Yes
With Irda Encoder/decoder
Yes
With False Start Bit Detection
Yes
With Modem Control
Yes
With Cmos
Yes
Mounting Type
Surface Mount
Data Rate
2 Mbps
Supply Voltage (max)
5.5 V
Supply Voltage (min)
2.97 V
Supply Current
3 mA to 6 mA
Maximum Operating Temperature
+ 70 C
Minimum Operating Temperature
0 C
Mounting Style
SMD/SMT
Operating Supply Voltage
2.97 V to 5.5 V
No. Of Channels
4
Uart Features
Tx/Rx FIFO Counters
Supply Voltage Range
2.97V To 5.5V
Operating Temperature Range
-40°C To +85°C
Digital Ic Case Style
QFP
Rohs Compliant
Yes
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Lead Free Status / RoHS Status
Lead free / RoHS Compliant, Lead free / RoHS Compliant
Other names
1016-1277
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
XR16C864IQ-F
Manufacturer:
NAIS
Quantity:
420
Company:
Part Number:
XR16C864IQ-F
Manufacturer:
Exar Corporation
Quantity:
10 000
XR16C864
2.97V TO 5.5V QUAD UART WITH 128-BYTE FIFO
Xoff characters
selected, the 864 compares two consecutive receive characters with two software flow control 8-bit values
(Xon1, Xon2, Xoff1, Xoff2) and controls TX transmissions accordingly. Under the above described flow control
mechanisms, flow control characters are not placed (stacked) in the user accessible RX data buffer or FIFO.
In the event that the receive buffer is overfilling and flow control needs to be executed, the 864 automatically
sends an Xoff message (when enabled) via the serial TX output to the remote modem. The 864 sends the Xoff-
1,2 characters two-character-times (= time taken to send two characters at the programmed baud rate) after
the receive FIFO crosses the programmed trigger level (for all trigger tables A-D). To clear this condition, the
864 will transmit the programmed Xon-1,2 characters as soon as receive FIFO is less than one trigger level
below the programmed trigger level (for Trigger Tables A, B, and C) or when receive FIFO is less than the
trigger level minus the hysteresis value (for Trigger Table D). This hysteresis value is the same as the Auto
RTS Hysteresis value in
* After the trigger level is reached, an xoff character is sent after a short span of time (= time required to send 2
A special character detect feature is provided to detect an 8-bit character when bit-5 is set in the Enhanced
Feature Register (EFR). When this character (Xoff2) is detected, it will be placed in the FIFO along with normal
incoming RX data.
The 864 compares each incoming receive character with Xoff-2 data. If a match exists, the received data will
be transferred to FIFO and ISR bit-4 will be set to indicate detection of special character. Although the Internal
Register Table shows Xon, Xoff Registers with eight bits of character information, the actual number of bits is
dependent on the programmed word length. Line Control Register (LCR) bits 0-1 defines the number of
character bits, i.e., either 5 bits, 6 bits, 7 bits, or 8 bits. The word length selected by LCR bits 0-1 also
determines the number of bits that will be used for the special character comparison. Bit-0 in the Xon, Xoff
Registers corresponds with the LSB bit for the receive character.
The auto RS485 half-duplex direction control changes the behavior of the transmitter when enabled by FCTR
bit-3. By default, it de-asserts OP1#/RS485 (logic 1) output following the last stop bit of the last character that
has been transmitted. This helps in turning around the transceiver to receive the remote station’s response.
When the host is ready to transmit next polling data packet again, it only has to load data bytes to the transmit
FIFO. The transmitter automatically re-asserts OP1#/RS485 (logic 0) output prior to sending the data.
The 864 UART includes the infrared encoder and decoder compatible to the IrDA (Infrared Data Association)
version 1.0. The IrDA 1.0 standard that stipulates the infrared encoder sends out a 3/16 of a bit wide HIGH-
pulse for each “0” bit in the transmit data stream. This signal encoding reduces the on-time of the infrared LED,
hence reduces the power consumption. See
The infrared encoder and decoder are enabled by setting MCR register bit-6 to a ‘1’. When the infrared feature
is enabled, the transmit data output, TX, idles at logic zero level. Likewise, the RX input assumes an idle level
of logic zero from a reset and power up, see
Typically, the wireless infrared decoder receives the input pulse from the infrared sensing diode on the RX pin.
Each time it senses a light pulse, it returns a logic 1 to the data bit stream. However, this is not true with some
characters); for example, after 2.083ms has elapsed for 9600 baud and 10-bit word length setting.
2.18
2.19
2.20
RX T
Infrared Mode
RIGGER
Special Character Detect
Auto RS485 Half-duplex Control
16
24
28
8
L
(See Table
EVEL
INT P
Table
17) and suspend/resume transmissions. When double 8-bit Xon/Xoff characters are
T
IN
ABLE
15.
A
16
24
28
8
CTIVATION
7: A
Table 7
UTO
below explains this when Trigger Table-B (See
X
Figure
Figure 11
ON
X
/X
(
OFF
CHARACTERS IN RX FIFO
OFF
11.
C
18
(S
HARACTER
below.
OFTWARE
16*
24*
28*
8*
(
S
) S
) F
ENT
LOW
)
C
ONTROL
X
(
CHARACTERS IN RX FIFO
ON
C
HARACTER
Table
16
24
0
8
áç
áç
áç
áç
11) is selected.
(
S
) S
ENT
REV. 2.0.1
)