UG-1262
Rev. B | Page 264 of 312
Bits Bit
Name
Settings
Description
Reset Access
3
FDMAMD
FIFO DMA Mode.
0x0
R/W
0
Receive DMA request is asserted when there is data in RBR in the COMRX register or the
receive FIFO, and deasserts when RBR or the receive FIFO is empty. A transmit DMA
request is asserted when THR in the COMTX register or the transmit FIFO is empty, and
deasserts whenever data is written to the COMTX register.
1
Receive DMA request is asserted when the receive FIFO trigger level or timeout is reached,
and deasserts when the receive FIFO is empty. The transmit DMA request is asserted
when the transmit FIFO is empty and deasserts when the transmit FIFO is completely full.
2
TFCLR
Clear Transmit FIFO.
0x0
W
0
No
effect.
1
Clear transmit FIFO.
1
RFCLR
Clear Receive FIFO.
0x0
W
0
No
effect.
1
Clear receive FIFO.
0
FIFOEN
FIFO Enabled to Work in 16550 UART Mode.
0x0
R/W
FRACTIONAL BAUD RATE REGISTER
Address: 0x40005024, Reset: 0x0000, Name: COMFBR
Table 331. Bit Descriptions for COMFBR
Bits
Bit
Name Settings Description
Reset Access
15 FBEN
Fractional Baud Rate Generator Enable. The generating of fractional baud rate and the
final baud rate of UART operation are calculated using the following:
0x0 R/W
Baud Rate
= ((
UCLK
)/(2 × (
M + N/
2048)) 16 ×
COMDIV
)
[14:13] Reserved
Reserved.
0x0 R
[12:11]
DIVM
Fractional Baud Rate M Divide Bits, 1 to 3. This bit must not be 0.
0x0
R/W
[10:0]
DIVN
Fractional Baud Rate N Divide Bits, 0 to 2047.
0x0
R/W
BAUD RATE DIVIDER REGISTER
Address: 0x40005028, Reset: 0x0000, Name: COMDIV
Table 332. Bit Descriptions for COMDIV
Bits Bit
Name
Settings
Description
Reset Access
[15:0] DIV
Baud Rate Divider. Ensure that the COMDIV register is not 0. The range of allowed DIV
values is from 1 to 65,535.
0x1 R/W
SECOND LINE CONTROL REGISTER
Address: 0x4000502C, Reset: 0x0002, Name: COMLCR2
Table 333. Bit Descriptions for COMLCR2
Bits Bit
Name Settings Description
Reset
Access
[15:2] Reserved
Reserved.
0x0 R
[1:0]
OSR
Over Sample Rate.
0x2
R/W
00
Over sample by 4.
01
Over sample by 8.
10
Over sample by 16.
11
Over sample by 32.