Bit
Name
Reset
Access Description
2:1
RXTO
0x0
RW
Receive Timeout.
This field defines the length of the timeout on the RX FIFO. If the RX FIFO is not empty but the number of bytes in the FIFO
is not enough to generate a Receive FIFO request, an RFRQ interrupt will be generated after the specified number of idle
frames. An "idle frame is defined as the length of a single transfer on the bus. For example, with a typical 8-N-1 configura-
tion there are 8 data bits, 1 start bit, and 1 stop bit per transfer. An "idle frame" with this configuration is 10 bit times at the
selected baud rate.
Value
Name
Description
0x0
DISABLED
The receive timeout feature is disabled.
0x1
TIMEOUT_2
A receive timeout will occur after 2 idle periods on the UART RX line.
0x2
TIMEOUT_4
A receive timeout will occur after 4 idle periods on the UART RX line.
0x3
TIMEOUT_16
A receive timeout will occur after 16 idle periods on the UART RX line.
0
RIE
1
RW
Receive Interrupt Enable.
This bit enables the RI flag to generate UART1 interrupts when there is information available in the receive FIFO, regard-
less of the RXTH settings.
Value
Name
Description
0
DISABLED
The RI flag will not generate UART1 interrupts.
1
ENABLED
The RI flag will generate UART1 interrupts when it is set.
20.4.9 UART1FCT: UART1 FIFO Count
Bit
7
6
5
4
3
2
1
0
Name
Reserved
TXCNT
Reserved
RXCNT
Access
R
R
R
R
Reset
0x0
0x0
0x0
0x0
SFR Page = 0x20; SFR Address: 0xFA
Bit
Name
Reset
Access Description
7:6
Reserved
Must write reset value.
5:4
TXCNT
0x0
R
TX FIFO Count.
This field indicates the number of bytes in the transmit FIFO.
3:2
Reserved
Must write reset value.
1:0
RXCNT
0x0
R
RX FIFO Count.
This field indicates the number of bytes in the receive FIFO.
EFM8UB3 Reference Manual
Universal Asynchronous Receiver/Transmitter 1 (UART1)
silabs.com
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