Baud Rate Generator Compare Registers 0 To 2 (Brgc0 To Brgc2) - NEC V850E/MS1 UPD703100 User Manual

(c) Baud rate error
The baud rate generator error is calculated as follows:

Actual
 
Error [%] =

Desired
(9,520/9,600 – 1) × 100 = –0.833 [%]
Example:
(5,000/4,800 – 1) × 100 = +4.167 [%]
(2) Allowable error range of baud rate
The allowable error range depends on the number of bits of one frame.
The basic limit is ±5% of baud rate error and ±4.5% of sample timing with an accuracy of 16 bits. However,
the practical limit should be ±2.3% of baud rate error, assuming that both the transmission and reception sides
contain an error.

10.4.2 Baud rate generator compare registers 0 to 2 (BRGC0 to BRGC2)

These are 8-bit compare registers used to set the timer count value for the BRG0 to BRG2.
These registers can be read/written in 8- or 1-bit units.
7 6
BRGC0 BRG07 BRG06
BRGC1 BRG17 BRG16
BRGC2 BRG27 BRG26
Caution Do not change the values in the BRGCn (n = 0 to 2) register by software during a
transmit/receive operation, because writing this register causes the internal timer (TMBRGn) to
be cleared.
CHAPTER 10 SERIAL INTERFACE FUNCTION
baud rate (baud rate with error)
baud rate (normal baud rate)
5 4 3
BRG05 BRG04 BRG03
BRG15 BRG14 BRG13
BRG25 BRG24 BRG23
User's Manual U12688EJ4V0UM00

  × 100
− 1

2 1 0
BRG02 BRG01 BRG00
BRG12 BRG11 BRG10
BRG22 BRG21 BRG20
Address After reset
FFFFF084H Undefined
FFFFF094H Undefined
FFFFF0A4H Undefined
313