EM78P809N
8-Bit Microcontroller
18
•
Product Specification (V1.0) 07.26.2005
(This specification is subject to change without further notice)
Bit 6 ~ Bit 5 ( UMODE1 ~ UMODE0 ) :
UART Transmission Mode Select Bit
UMODE1
UMODE0
UART Mode
0 0
Mode1:
7-bits
0 1
Mode2:
8-bits
1 0
Mode3:
9-bits
1 1
Reserved
Bit 4 ~ Bit 2 ( BRATE2 ~ BRATE1 ) :
Transmit Baud Rate Select
BRATE2
BRATE1
BRATE0
Baud Rate
e.g. Fc=8MHz
0 0 0
Fc/13
38400
0 0 1
Fc/26
19200
0 1 0
Fc/52
9600
0 1 1
Fc/104
4800
1 0 0
Fc/208
2400
1 0 1
Fc/416
1200
1 1 0
TC4
1 1 1
Fc/96
Bit 1 ( UTBE ) :
UART transfer buffer empty flag. Set to 1 when transfer buffer is
empty. Reset to 0 automatically when writing into the URTD register. UTBE bit will
be cleared by hardware when enabling the transmission. UTBE bit is read-only.
Therefore, writing to the URTD register is necessary when we want to start
transmission shifting.
Bit 0 ( TXE )
: Enable transmission
TXE
=
“0”
:
Disable
TXE
=
“1”
:
Enable
URC2
−
UART Control Register 2 ( Address: 06h )
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0 0
SBIM1
SBIM0
UINVEN
0 0 0
Bit 5 ~ Bit 4 ( SBIM1 ~ SBIM0 ) :
Serial bus interface operation mode select.
TC2CK1
TC2CK0
Operation Mode
0 0
I/O
mode
0 1
SPI
mode
1 0
UART
mode
1 1
Reserved
Bit 3 ( UINVEN ) :
Enable UART TXD and RXD port inverse output.
UINVEN = “0” :
Disable TXD and RXD port inverse output.
UINVEN = “1” :
Enable TXD and RXD port inverse output.