at89c51ic2-slsim ATMEL Corporation, at89c51ic2-slsim Datasheet - Page 51

• Manufacturer Part Number: at89c51ic2-slsim
• Description: At89c51ic2 8-bit Flash Microcontroller With 2-wire Interface
• Manufacturer: ATMEL Corporation

Internal Baud Rate Generator
(BRG)
Figure 21. Internal Baud Rate
4301D–8051–02/08
Peripheral clock
BRR
When the internal Baud Rate Generator is used, the Baud Rates are determined by the
BRG overflow depending on the BRL reload value, the value of SPD bit (Speed Mode)
in BDRCON register and the value of the SMOD1 bit in PCON register.
•
The baud rate for UART is token by formula:
BaudRate
(
BRL
/6
)
=
256
SPD
0
1
=
auto reload counter
--------------------------------------------------------------------------------------------------------- -
2
–
×
---------------------------------------------------------------------------------------- -
2 2
2 6
×
×
2
×
〈
SMOD1
2
6
1 SPD
BRG
BRL
SMOD
(
1 SPD
–
–
×
×
overflow
〉
F
)
F
×
×
CLKPERIPH
CLKPERIPH
16
16
×
×
[
BaudRate
256
–
/2
(
BRL
)
]
0
1
INT_BRG
51