BAUD — Baud Rate
$102B
Bit 7
6
0
0
5
SCP1
0
4
SCP0
0
3
RCKB
0
2
SCR2
U
1
SCR1
U
Bit 0
SCR0
U
TCLR
RESET:
0
TCLR — Clear Baud Rate Counters (TEST)
SCP1, SCP0 — SCI Baud Rate Prescaler Selects
Divide
Crystal Frequency in MHz
Internal
Clock
By
4.0 MHz
(Baud)
8.0 MHz
(Baud)
10.0 MHz
(Baud)
12.0 MHz
(Baud)
SCP[1:0]
00
01
10
11
1
3
62.50K
20.83K
15.625K
4800
125.0K
41.67K
31.25K
9600
156.25K
52.08K
38.4K
187.5K
62.5K
4
46.88K
14.42K
13
12.02K
RCKB — SCI Baud Rate Clock Check (TEST)
SCR2, SCR1, and SCR0 — SCI Baud Rate Selects
Selects receiver and transmitter bit rate based on output from baud rate prescaler stage.
Divide
Prescaler
By
Highest Baud Rate
(Prescaler Output from Previous Table)
SCP[2:0]
4800
4800
2400
1200
600
300
150
—
9600
9600
4800
2400
1200
600
38.4K
38.4K
19.2K
9600
4800
2400
1200
600
000
001
010
011
100
101
110
111
1
2
4
8
16
32
64
128
300
150
—
—
300
MC68HC11A8
MC68HC11A8TS/D
MOTOROLA
25
MOTOROLA [ MOTOROLA ]
