DA14580_16 Datasheet, PDF (67/155 Pages) Dialog Semiconductor – Bluetooth Low Energy 4.2 SoC

DA14580
Bluetooth Low Energy 4.2 SoC
FINAL
Table 87: UART2_RBR_THR_DLL_REG (0x50001100)
Bit
Mode Symbol
7:0
R/W RBR_THR_DLL
Description
Receive Buffer Register: This register contains the data byte
received on the serial input port (sin) in UART mode or the
serial infrared input (sir_in) in infrared mode. The data in this
register is valid only if the Data Ready (DR) bit in the Line
status Register (LSR) is set. If FIFOs are disabled (FCR[0]
set to zero), the data in the RBR must be read before the
next data arrives, otherwise it will be overwritten, resulting in
an overrun error. If FIFOs are enabled (FCR[0] set to one),
this register accesses the head of the receive FIFO. If the
receive FIFO is full and this register is not read before the
next data character arrives, then the data already in the
FIFO will be preserved but any incoming data will be lost. An
overrun error will also occur. Transmit Holding Register: This
register contains data to be transmitted on the serial output
port (sout) in UART mode or the serial infrared output
(sir_out_n) in infrared mode. Data should only be written to
the THR when the THR Empty (THRE) bit (LSR[5]) is set. If
FIFO's are disabled (FCR[0] set to zero) and THRE is set,
writing a single character to the THR clears the THRE. Any
additional writes to the THR before the THRE is set again
causes the THR data to be overwritten. If FIFO's are enabled
(FCR[0] set to one) and THRE is set, x number of characters
of data may be written to the THR before the FIFO is full.
The number x (default=16) is determined by the value of
FIFO Depth that you set during configuration. Any attempt to
write data when the FIFO is full results in the write data being
lost. Divisor Latch (Low): This register makes up the lower 8-
bits of a 16-bit, read/write, Divisor Latch register that con-
tains the baud rate divisor for the UART. This register may
only be accessed when the DLAB bit (LCR[7]) is set. The
output baud rate is equal to the serial clock (sclk) frequency
divided by sixteen times the value of the baud rate divisor, as
follows: baud rate = (serial clock freq) / (16 * divisor) Note
that with the Divisor Latch Registers (DLL and DLH) set to
zero, the baud clock is disabled and no serial communica-
tions will occur. Also, once the DLL is set, at least 8 clock
cycles of the slowest DW_apb_uart clock should be allowed
to pass before transmitting or receiving data.
Reset
0x0
Table 88: UART2_IER_DLH_REG (0x50001104)
Bit
Mode Symbol
15:8 -
-
7
R/W PTIME_DLH7
6:4
-
-
3
R/W EDSSI_DLH3
Description
Reserved
Interrupt Enable Register: PTIME, Programmable THRE
Interrupt Mode Enable. This is used to enable/disable the
generation of THRE Interrupt. 0 = disabled 1 = enabled Divi-
sor Latch (High): Bit[7] of the 8 bit DLH register.
Reserved
Interrupt Enable Register: EDSSI, Enable Modem Status
Interrupt. This is used to enable/disable the generation of
Modem Status Interrupt. This is the fourth highest priority
interrupt. 0 = disabled 1 = enabled Divisor Latch (High):
Bit[3] of the 8 bit DLH register
Reset
0x0
0x0
0x0
0x0
Datasheet
CFR0011-120-01
Revision 3.4
67 of 155
09-Nov-2016
© 2014 Dialog Semiconductor