MC68HC11PH8 Datasheet, PDF (99/264 Pages) Motorola, Inc – High-density Complementary Metal Oxide Semiconductor (HCMOS) Microcomputer Unit

Table 5-1 Example SCI baud rate control values
Target
baud
rate
ST4XCK frequency
8 MHz
12 MHz
16 MHz
Dec value Hex value Dec value Hex value Dec value Hex value
110
2272 $08E0 3409 $0D51 4545 $11C1
150
1666 $0682 2500 $09C4 3333 $0D05
300
833 $0341 1250 $04E2 1666 $0682
600
416 $01A0 625 $0271 833 $0341
1 200
208 $00D0 312
$0138
416 $01A0
2 400
104
$0068
156 $009C 208 $00D0
4 800
52
$0034
78
$004E 104 $0068
5
9 600
26
$001A
39
$0027
52
$0034
19 200
13
$000D
20
$0014
26
$001A
38 400
13
$000D
5.6.2 SCCR1 — SCI control register 1
SCI1 control 1 (SCCR1)
Address bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
State
on reset
$0072 LOOPS WOMS 0
M WAKE ILT PE PT 0000 0000
The SCCR1 register provides the control bits that determine word length and select the method
used for the wake-up feature.
LOOPS — SCI loop mode enable
1 (set) – SCI transmit and receive are disconnected from TXD and RXD pins,
and transmitter output is fed back into the receiver input.
0 (clear) – SCI transmit and receive operate normally.
Both the transmitter and receiver must be enabled to use the LOOP mode. When the LOOP mode
is enabled, the TXD pin is driven high (idle line state) if the transmitter is enabled.
WOMS — Wired-OR mode for SCI pins (PD1, PD0)
1 (set) – TXD and RXD are open drains if operating as outputs.
0 (clear) – TXD and RXD operate normally.
Bit 5 — Not implemented; always reads zero
MC68HC11PH8
SERIAL COMMUNICATIONS INTERFACE
TPG
MOTOROLA
5-7