XR18W750 ON Semiconductor, XR18W750 Datasheet - Page 30

• Manufacturer Part Number: XR18W750
• Manufacturer: ON Semiconductor

XR18W750
WIRELESS UART CONTROLLER
EMSR[1:0]: Receive/Transmit FIFO Level Count (Write-Only)
When Scratchpad Swap (FCTR[6]) is asserted, EMSR bits 1-0 controls what mode the FIFO Level Counter is
operating in.
During Alternate RX/TX FIFO Level Counter Mode, the first value read after EMSR bits 1-0 have been
asserted will always be the RX FIFO Level Counter. The second value read will correspond with the TX FIFO
Level Counter. The next value will be the RX FIFO Level Counter again, then the TX FIFO Level Counter and
so on and so forth.
EMSR[3:2]: Reserved
For normal operation, these bits should be ’0’.
EMSR[5:4]: Extended RTS Hysteresis
FCTR[6] EMSR[1] EMSR[0] Scratchpad is
0
1
1
1
EMSR
B
IT
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
X
X
0
1
-5
T
ABLE
T
ABLE
EMSR
B
12: S
IT
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
X
0
1
1
-4
13: A
CRATCHPAD
Scratchpad
RX FIFO Level Counter Mode
TX FIFO Level Counter Mode
Alternate RX/TX FIFO Counter Mode
FCTR
B
UTO
IT
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
-1
30
RTS H
S
FCTR
B
WAP
IT
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
YSTERESIS
-0
S
ELECTION
(C
H
HARACTERS
YSTERESIS
RTS#
±16
±24
±32
±40
±44
±48
±52
±12
±20
±28
±36
±4
±6
±8
±8
0
)
REV. 1.0.0