Rev. 1.10
162
October 23, 2020
Rev. 1.10
163
October 23, 2020
BC66F5652
2.4GHz RF Transceiver A/D Flash MCU
BC66F5652
2.4GHz RF Transceiver A/D Flash MCU
Bit 6
NF
: Noise flag
0: No noise is detected
1: Noise is detected
The NF flag is the noise flag. When this read only flag is “
0”, it indicates no noise
condition. When the flag is “
1”, it indicates that the UART has detected noise on the
receiver input. The NF flag is set during the same cycle as the RXIF flag but will
not be set in the case of as overrun. The NF flag can be cleared
to zero by a software
sequence which will involve a read to the status register USR followed by an access to
the TXR_RXR data register.
Bit 5
FERR
: Framing error flag
0: No framing error is detected
1: Framing error is detected
The FERR flag is the framing error flag. When this read only flag is “0”, it indicates
that there is no framing error. When the flag is “1”, it indicates that a framing error
has been detected for the current character. The flag can also be cleared to zero by a
software sequence which will involve a read to the status register USR followed by an
access to the TXR_RXR data register.
Bit 4
OERR
: Overrun error flag
0: No overrun error is detected
1: Overrun error is detected
The OERR flag is the overrun error flag which indicates when the receiver buffer
has overflowed. When this read only flag is “
0”, it indicates that there is no overrun
error. When the flag is “1
”, it indicates that an overrun error occurs which will inhibit
further transfers to the TXR_RXR receive data register. The flag is cleared
to zero by a
software sequence, which is a read to the status register USR followed by an access to
the TXR_RXR data register.
Bit 3
RIDLE
: Receiver status
0: Data reception is in progress (Data being received)
1: No data reception is in progress (Receiver is idle)
The RIDLE flag is the receiver status flag. When this read only flag is “
0”, it indicates
that the receiver is between the initial detection of the start bit and the completion of
the stop bit. When the flag is “
1”, it indicates that the receiver is idle. Between the
completion of the stop bit and the detection of the next start bit, the RIDLE bit is
“
1”
indicating that the UART receiver is idle and the RX pin stays in logic high condition.
Bit 2
RXIF
: Receive TXR_RXR data register status
0: TXR_RXR data register is empty
1: TXR_RXR data register has available data
The RXIF flag is the receive data register status flag. When this read only flag is “
0”,
it indicates that the TXR_RXR read data register is empty. When the flag is
“
1”, it
indicates that the TXR_RXR read data register contains new data. When the contents
of the shift register are transferred to the TXR_RXR register, an interrupt is generated
if RIE=1 in the UCR2 register. If one or more errors are detected in the received word,
the appropriate receive-related flags NF, FERR, and/or PERR are set within the same
clock cycle. The RXIF flag will eventually be cleared
to zero when the USR register is
read with RXIF set, followed by a read from the TXR_RXR register, and if the TXR_
RXR register has no more new data available.
Bit 1
TIDLE
: Transmission idle
0: Data transmission is in progress (Data being transmitted)
1: No data transmission is in progress (Transmitter is idle)
The TIDLE flag is known as the transmission complete flag. When this read only
flag is
“
0”, it indicates that a transmission is in progress. This flag will be set high
when the TXIF flag is “1”
and when there is no transmit data or break character being
transmitted. When TIDLE is equal to
“1”
, the TX pin becomes idle with the pin state
in logic high condition. The TIDLE flag is cleared
to zero by reading the USR register
with TIDLE set and then writing to the TXR_RXR register. The flag is not generated
when a data character or a break is queued and ready to be sent.