F71862
FIFO Control Register Base + 2
Bit Name R/W Default
Description
00: Receiver FIFO trigger level is 1.
01: Receiver FIFO trigger level is 4.
10: Receiver FIFO trigger level is 8.
7-6 RCV_TRIG
W
00
11: Receiver FIFO trigger level is 14.
5-3 Reserved
-
-
Reserved.
Reset the transmitter FIFO.
2
1
0
CLRTX
R
R
R
0
0
0
Reset the receiver FIFO.
CLRRX
FIFO_EN
0: Disable FIFO.
1: Enable FIFO.
Line Control Register Base + 3
Bit
Name
R/W Default
Description
0: Divisor Latch can’t be accessed.
1: Divisor Latch can be accessed via Base and Base+1.
0: Transmitter is in normal condition.
1: Transmit a break condition.
XX0: Parity Bit is disable
7
DLAB
R/W
0
6
SETBRK
R/W
0
5
4
3
STKPAR
EPS
R/W
R/W
R/W
0
0
0
001: Parity Bit is odd.
011: Parity Bit is even
PEN
101: Parity Bit is logic 1
111: Parity Bit is logic 0
0: Stop bit is one bit
1: When word length is 5 bit stop bit is 1.5 bit
else stop bit is 2 bit
2
STB
R/W
R/W
0
00: Word length is 5 bit
1-0 WLS
00
01: Word length is 6 bit
10: Word length is 7 bit
11: Word length is 8 bit
MODEM Control Register Base + 4
Bit
Name
R/W Default
Description
Reserved.
7-5 Reserved
-
-
0: UART in normal condition.
1: UART is internal loop back
0: All interrupt is disabled.
4
3
LOOP
OUT2
R/W
0
R/W
0
1: Interrupt is enabled
(disabled) by IER.
Read from MSR[6] is loop back mode
2
1
OUT1
RTS
R/W
R/W
0
0
0: RTS# is forced to logic 1
1: RTS# is forced to logic 0
0: DTR# is forced to logic 1
1: DTR# is forced to logic 0
0
DTR
R/W
0
Line Status Register Base + 5
Bit
Name
RCR_ERR
R/W Default
Description
0: No error in the FIFO when FIFO is enabled
1: Error in the FIFO when FIFO is enabled.
0: Transmitter is in transmitting.
7
R
0
6
TEMT
R
1
1: Transmitter is empty.
34
July, 2008
V.28P