89C51IC2-CM ATMEL [ATMEL Corporation], 89C51IC2-CM Datasheet - Page 51

• Manufacturer Part Number: 89C51IC2-CM
• Description: 8-bit Flash Microcontroller with 2-wire Interface
• Manufacturer: ATMEL [ATMEL Corporation]

Internal Baud Rate Generator
(BRG)
Figure 21. Internal Baud Rate
4301A–8051–01/04
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 1 SPD
2
〈
SMOD 1
2
6
BRG
BRL
SMOD
1 SPD
–
–
overflow
〉
F
F
CLKPERIPH
CLKPERIPH
16
16
BaudRate
256
–
/2
BRL
0
1
AT89C51IC2
INT_BRG
51