397
The method of calculating the value from the operating frequency and bit rate, on the other hand,
is shown below. N is an integer, 0
≤
N
≤
255, and the smaller error is specified.
N =
ø
1488
×
2
2n–1
×
B
×
10
6
– 1
Table 12-6 Examples of BRR Settings for Bit Rate B (bit/s) (When n = 0)
ø (MHz)
7.1424
10.00
10.7136
13.00
14.2848
16.00
18.00
bit/s
N
Error
N
Error
N
Error
N
Error
N
Error
N
Error
N
Error
9600
0
0.00
1
30
1
25
1
8.99
1
0.00
1
12.01
2
15.99
Table 12-7 Maximum Bit Rate at Various Frequencies (Smart Card Interface Mode)
ø (MHz)
Maximum Bit Rate (bit/s)
N
n
7.1424
9600
0
0
10.00
13441
0
0
10.7136
14400
0
0
13.00
17473
0
0
14.2848
19200
0
0
16.00
21505
0
0
18.00
24194
0
0
The bit rate error is given by the following formula:
Error (%) = (
ø
1488
×
2
2n–1
×
B
×
(N + 1)
×
10
6
– 1)
×
100