SH7018 Datasheet, PDF (238/431 Pages) Renesas Technology Corp – SuperH™ RISC engine

The BRR1 setting is calculated as follows:
Asynchronous mode:
N
=
64
×
φ
2^2n–1
×
B
×
10⁶
–
1
Clock synchronous mode:
N=
φ
8 × 2^2n–1 × B
× 10⁶ – 1
B: Bit rate (bit/s)
N: Baud rate generator BRR1 setting (0 ≤ N ≤ 255)
φ: Operating frequency (MHz)
n: Baud rate generator input clock (n = 0 to 3)
(See the following table for the clock sources and value of n.)
SMR1 Settings
n
Clock Source
CKS1
CKS2
0
φ
0
0
1
φ/4
0
1
2
φ/16
1
0
3
φ/64
1
1
The bit rate error in asynchronous mode is calculated as follows:
Error
(%)

= _{(N}
+
1)
φ × 10⁶
× B × 64
×
2^2n–1
–
1
× 100
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