NEC UPD703116 User Manual page 440

Therefore, the transfer destination's maximum baud rate (BRmax) that can be received is as follows.
Similarly, the maximum allowable transfer rate (FLmax) can be obtained as follows.
Therefore, the transfer destination's minimum baud rate (BRmin) that can be received is as follows.
The allowable baud rate error of UART0 and the transfer destination can be obtained as follows from the
expressions described above for computing the minimum and maximum baud rate values.
Table 10-4. Maximum and Minimum Allowable Baud Rate Error
Division Ratio (k)
8
20
50
100
255
Remarks 1. The reception precision depends on the number of bits in one frame, the base clock frequency,
and the division ratio (k). The higher the base clock frequency and the larger the division ratio
(k), the higher the precision.
2. k: BRGC0 register setting value
440
CHAPTER 10 SERIAL INTERFACE FUNCTION
−
1
BRmax = (FLmin/11)
10 k
× = × −
FL max 11 FL
11 2
−
21 k 2
= ×
FL max FL
20 k
−
1
BRmin = (FLmax/11)
Maximum Allowable
Baud Rate Error
+3.53%
+4.26%
+4.56%
+4.66%
+4.72%
User's Manual U14492EJ5V0UD
22k
= Brate
21k + 2
+ −
2 21 k 2
× =
FL FL
× ×
k 2 k
11
20k
= Brate
21k − 2
Minimum Allowable
Baud Rate Error
–3.61%
–4.31%
–4.58%
–4.67%
–4.73%