UART/IrDA Control and Status Registers
12-81
UART Devices
With an input frequency of 12 MHz:
At 115200 bauds
DLH = 0x00
DLL = 0x01
MDR24:3 = 0x00
DIV_1.6 = 0x01
At 57600 bauds
DLH = 0x00
DLL = 0x02
MDR24:3 = 0x00
DIV_1.6 = 0x14
At 38400 bauds
DLH = 0x00
DLL = 0x03
MDR24:3 = 0x00
DIV_1.6 = 0x27
At 19200 bauds
DLH = 0x00
DLL = 0x06
MDR24:3 = 0x00
DIV_1.6 = 0x62
At 9600 bauds
DLH = 0x00
DLL = 0x0C
MDR24:3 = 0x00
DIV_1.6 = 0xD7
At 2400 bauds
DLH = 0x01
DLL = 0x30
MDR24:3 = 0x03
DIV_1.6 = 0x96
Table 12–85. Auxiliary Control Register (ACREG)
Bit
Name
Value
Function
R/W
Reset
Value
7
PULSE_TYPE
SIR pulse-width select:
R/W
0
0
3/16 of baud-rate pulse width
1
1.6-
µ
s
6
SD_MOD
Primary output used to configure
transceivers. Connected to the SD/MODE
input of transceivers.
R/W
0
0
SD_MODE pin is set to high.
1
SD_MODE pin is set to low.
5
DIS_IR_RX
0
Enables RXIR input
R/W
0
1
Disables RXIR input for half-duplex
purpose
4
DIS_TX_UNDERRUN
0
Long stop bits cannot be transmitted, TX
underrun is enabled.
R/W
0
1
Long stop bits can be transmitted, TX
underrun is disabled.
3
–
Reserved
R
0
2
SCTX_EN
Store and controlled TX start. When
MDR15 = 1 and the host writes 1 to this bit,
the TX state machine starts frame
transmission. This bit is self-clearing.
R/W
0