Z8F4822AR020SG Datasheet, PDF (126/323 Pages) Zilog, Inc. – High Performance 8-Bit Microcontrollers

Z8 Encore! XP^® F64xx Series
Product Specification
106
Table 60. UART Baud Rate High Byte Register (UxBRH)
Bit
7
6
5
4
3
2
1
0
Field
BRH
RESET
1
R/W
R/W
Address
F46H and F4EH
Table 61. UART Baud Rate Low Byte Register (UxBRL)
Bit7
7
6
5
4
3
2
1
0
Field
BRL
RESET
1
R/W
R/W
Address
F47H and F4FH
For a given UART data rate, the integer baud rate divisor value is calculated using the fol-
lowing equation:
UART Baud Rate Divisor Value (BRG) = Round_-S1---y6---s-_-t--e--U-m----A--C--R--l-o-T--c---Dk----a-F--t-r-a-e---qR---u-a--e-t-en---c-(--yb---i--(t--Hs--/--sz--)-)_
The baud rate error relative to the appropriate baud rate is calculated using the following
equation:
UART Baud Rate Error
(%)
=
100



A-----c--t--u---a---l---D----a--D-t--a--e--Rs---i-ar--e-t-e-d---–-D----D-a--t-e-a--s--Ri--r--ea---dt--e--D----a---t--a----R----a---t-e- _
For reliable communication, the UART baud rate error must never exceed 5 percent.
Table 62 lists data rate errors for popular baud rates and commonly used crystal oscillator
frequencies.
PS019924-0113
PRELIMINARY
UART Control Register Definitions