Z8F1680SH020SG Datasheet, PDF (204/412 Pages) Zilog, Inc. – High-Performance 8-Bit Microcontrollers

Z8 Encore! XP^® F1680 Series
Product Specification
179
For a given LIN-UART data rate, the integer baud rate divisor value is calculated using the
following equation for LIN mode UART operation:
UART
Baud Rate Divisor Value
(BRG)
=
Ro
und


S-----y---sU--t--eA----mR-----T-C----D-l-o--a-c---tk-a----F-R---r--ea---qt--e-u----e(--b-n--i-ct--s-y--/--s-(--)H----z---)-_
The baud rate error relative to the appropriate baud rate is calculated using the following
equation:
ot
UART Baud Rate Error (%) = 100  _^{A----c----t-u----a---l---D----a---D-t-a---e--R-s---i-ar--e-t--e-d---–}--D---D-a---te--a--s---iR-r--e-a--d--t-e--D-----a---t--a-----R----a---t--e--_
For reliable communication, the LIN-UART baud rate error must never exceed 5 percent.
Tables 96 through 100 provide error data for popular baud rates and commonly-used crys-
tal oscillator frequencies for normal UART modes of operation.
Table 96. LIN-UART Baud Rates, 20.0 MHz System Clock
Applicable
Rate (kHz)
1250.0
625.0
250.0
115.2
57.6
38.4
19.2
BRG
Divisor Actual Rate
(Decimal) (kHz) Error (%)
1
1250.0
0.00
2
625.0
0.00
5
250.0
0.00
11
113.64
–1.19
22
56.82
–1.36
33
37.88
–1.36
65
19.23
0.16
BRG
Applicable Divisor Actual Rate
Rate (kHz) (Decimal) (kHz) Error (%)
9.60
130
9.62
0.16
4.80
260
4.81
0.16
2.40
521
2.399
–0.03
1.20
1042
1.199
–0.03
0.60
2083
0.60
0.02
0.30
4167
0.299
–0.01
Table 97. LIN-UART Baud Rates, 10.0 MHz System Clock
BRG
Applicable Divisor Actual Rate
Rate (kHz) (Decimal) (kHz) Error (%)
1250.0
N/A
N/A
N/A
625.0
1
625.0
0.00
250.0
3
208.33 –16.67
115.2
5
125.0
8.51
57.6
11
56.8
–1.36
BRG
Applicable Divisor Actual Rate
Rate (kHz) (Decimal) (kHz) Error (%)
9.60
65
9.62
0.16
4.80
130
4.81
0.16
2.40
260
2.40
–0.03
1.20
521
1.20
–0.03
0.60
1042
0.60
–0.03
PS025015-1212
PRELIMINARY
LIN-UART