Rev. 1.50
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Rev. 1.50
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HT66F0175/HT66F0185
A/D Flash MCU with EEPROM
HT66F0175/HT66F0185
A/D Flash MCU with EEPROM
UCR1 Register
The UCR1 register together with the UCR2 register are the UART control registers that are used
to set the various options for the UART function such as overall on/off control, parity control, data
transfer bit length, etc. Further explanation on each of the bits is given below.
Bit
7
6
5
4
3
2
1
0
Name
U�RTEN
BNO
PREN
PRT
STOPS
TXBRK
RX�
TX�
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R
W
POR
0
0
0
0
0
0
x
0
“x”: �nknown
Bit 7
UARTEN
: UART function enable control
0: Disable UART; TX and RX pins are used as other pin-shared functional pins.
1: Enable UART; TX and RX pins can function as UART pins defined by TXEN and
RXEN bits
The UARTEN bit is the UART enable bit. When this bit is equal to “0”, the UART will
be disabled and the RX pin as well as the TX pin will be other pin-shared functional
pins. When the bit is equal to “1”, the UART will be enabled and the TX and RX pins
will function as defined by the TXEN and RXEN enable control bits. When the UART
is disabled, it will empty the buffer so any character remaining in the buffer will be
discarded. In addition, the value of the baud rate counter will be reset. If the UART
is disabled, all error and status flags will be reset. Also the TXEN, RXEN, TXBRK,
RXIF, OERR, FERR, PERR and NF bits will be cleared, while the TIDLE, TXIF and
RIDLE bits will be set. Other control bits in UCR1, UCR2 and BRG registers will
remain unaffected. If the UART is active and the UARTEN bit is cleared, all pending
transmissions and receptions will be terminated and the module will be reset as defined
above. When the UART is re-enabled, it will restart in the same configuration.
Bit 6
BNO
: Number of data transfer bits selection
0: 8-bit data transfer
1: 9-bit data transfer
This bit is used to select the data length format, which can have a choice of either
8-bit or 9-bit format. When this bit is equal to “1”, a 9-bit data length format will be
selected. If the bit is equal to “0”, then an 8-bit data length format will be selected. If
9-bit data length format is selected, then bits RX8 and TX8 will be used to store the 9
th
bit of the received and transmitted data respectively.
Bit 5
PREN
: Parity function enable control
0: Parity function is disabled
1: Parity function is enabled
This bit is the parity function enable bit. When this bit is equal to 1, the parity function
will be enabled. If the bit is equal to 0, then the parity function will be disabled.
Bit 4
PRT
: Parity type selection bit
0: Even parity for parity generator
1: Odd parity for parity generator
This bit is the parity type selection bit. When this bit is equal to 1, odd parity type will
be selected. If the bit is equal to 0, then even parity type will be selected.
Bit 3
STOPS
: Number of stop bits selection
0: One stop bit format is used
1: Two stop bits format is used
This bit determines if one or two stop bits are to be used. When this bit is equal to “1”,
two stop bits format are used. If the bit is equal to “0”, then only one stop bit format is
used.