XR18W750/753-0B-EB Exar Corporation, XR18W750/753-0B-EB Datasheet - Page 15

• Manufacturer Part Number: XR18W750/753-0B-EB
• Description: EVAL BOARD FOR XR18W750/753
• Manufacturer: Exar Corporation

Specifications of XR18W750/753-0B-EB

• Silicon Manufacturer: Exar
• Silicon Core Number: XR18W750
• Kit Application Type: Communication & Networking
• Application Sub Type: Wireless UART Controller
• Kit Contents: Board
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

REV. 1.0.0
N
Automatic RTS hardware flow control is used to prevent data overrun to the local receiver FIFO. The RTS#
output is used to request remote unit to suspend/resume data transmission. The auto RTS flow control
features is enabled to fit specific application requirement (see
•
•
If using the Auto RTS interrupt:
•
With the Auto RTS function enabled, an interrupt is generated when the receive FIFO reaches the
programmed RX trigger level. The RTS# pin will not be forced HIGH (RTS off) until the receive FIFO reaches
the upper limit of the hysteresis level. The RTS# pin will return LOW after the RX FIFO is unloaded to the lower
limit of the hysteresis level. Under the above described conditions, the enhanced UART will continue to accept
data until the receive FIFO gets full. The Auto RTS function is initiated when the RTS# output pin is asserted
LOW (RTS On).
this table is for programmable trigger levels only (Table D). The hysteresis values for Tables A-C are the next
higher and next lower trigger levels in the corresponding table.
F
3.11
3.12
OTE
IGURE
Enable auto RTS flow control using EFR bit-6.
The auto RTS function must be started by asserting RTS# output pin (MCR bit-1 to logic 1 after it is enabled).
Enable RTS interrupt through IER bit-6 (after setting EFR bit-4). The UART issues an interrupt when the
RTS# pin makes a transition from low to high: ISR bit-5 will be set to logic 1.
Receive Data
Byte and Errors
: Table-B selected as Trigger Table for
64 bytes by 11-bit
8. R
Auto RTS (Hardware) Flow Control
Auto RTS Hysteresis
16X Clock
wide
FIFO
ECEIVER
Table 13
O
PERATION IN
shows the complete details for the Auto RTS# Hysteresis levels. Please note that
Receive Data Shift
Register (RSR)
Data FIFO
Receive
Receive
FIFO
Data
Figure 8
AND
A
Data fills to 24
Data falls to 8
UTO
Validation
Trigger=16
Data Bit
(
FIFO
Table 10
Example
RTS F
: - RX FIFO trigger level selected at 16 bytes
15
LOW
).
(See Note Below)
Enable by EFR bit-6=1, MCR bit-1.
Enable by EFR bit-6=1, MCR bit-1.
Figure
RTS# re-asserts when data falls below the flow
control trigger level to restart remote transmitter.
RTS# de-asserts when data fills above the flow
desired FIFO trigger level.
control trigger level to suspend remote transmitter.
FIFO is Enabled by FCR bit-0=1
C
RHR Interrupt (ISR bit-2) programmed for
ONTROL
9):
M
WIRELESS UART CONTROLLER
ODE
Receive Data Characters
XR18W750
RXFIFO1