
W83877AF
Publication Release Date: Sep. 1996
Preliminary Version 0.50
- 57 -
FEND_I - Frame End Interrupt.
Set to 1 when (1) a frame have a grace end to be detected where the frame signal is
defined in the physical layer of IrDA version 1.1 (2) abort signal or illegal signal has been
detected during receiving valid data. Clear to 0 when this register is read.
Remote Controller mode:
Not used.
TXEMP_I - Transmitter Empty.
Set to 1 when transmitter (or, say, FIFO + Transmitter) is empty. Clear to 0 when this
register is read.
RXTH_I - Receiver Threshold Interrupt.
Set to 1 when (1) the Receiver Buffer Register (RBR) is equal
or
larger than the threshold
level, (2) RBR occurs time-out if the receiver buffer register has valid data and below the
threshold level. Clear to 0 when RBR is less than threshold level from reading RBR.
Bit 1:
Bit 0:
(2) UART FIFO Control Register (UFR):
Mode
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Legacy
UART
RXFTL1
(MSB)
RXFTL0
(LSB)
0
0
0
TXF_RST RXF_RST EN_FIFO
Advanced
UART
RXFTL1
(MSB)
RXFTL0
(LSB)
TXFTL1
(MSB)
TXFTL0
(LSB)
0
TXF_RST RXF_RST EN_FIFO
Reset Value
0
0
0
0
0
0
0
0
Legacy UART:
The definition of this register is same as Legacy UART mode.
Advanced UART:
Bit 7, 6:
RXFTL1, 0 - Receiver FIFO Threshold Level
Definition is same as Legacy UART, that is to determine the RXTH_I to become 1 when
the Receiver FIFO Threshold Level is equal or larger than the defined value shown as
follow.
RXFTL1, 0
(Bit 7, 6)
RX FIFO Threshold Level
(
FIFO Size:
16-byte
)
1
RX FIFO Threshold Level
(
FIFO Size:
32-byte
)
1
00
01
4
4
10
8
16
11
14
26
Note that the FIFO Size is referred to SET2.Reg4.
Bit 5, 4:
TXFTL1, 0 - Transmitter FIFO Threshold Level
To determine the TXTH_I (Transmitter Threshold Level Interrupt) is set to 1 when the
Transmitter Threshold Level is less than the programmed value shown as follows.