Note: If possible, the error should be within 1%.
F
F
B =
× 106
N =
× 106 – 1
64 × 22n–1 × (N + 1)
64 × 22n–1 × B
B: Bit rate (bits/second)
N: Baud rate generator BRR value (0 ≤ N ≤ 255)
F: øP (MHz) when n ≠ 0, or ø (MHz) when n = 0
n: Baud rate generator input clock (n = 0, 1, 2, 3)
The meaning of n is given below.
SMR
CKS0
WSCR
n
0
1
2
3
0
1
2
3
CKS1
CKDBL
Clock
ø
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
0
0
0
0
1
1
1
1
ø/4
ø/16
ø/64
ø
ø/8
ø/32
ø/128
The bit rate error can be calculated with the formula below.
F × 106
× 100
– 1
Error (%) =
(N + 1) × B × 64 × 22n–1
252