MC68HC11KW1 Datasheet, PDF (135/238 Pages) Motorola, Inc – High-density complementary metal oxide semiconductor HCMOS) microcontroller unit

Table 7-1 Example SCI baud rate control values
Target baud
rate
110
150
300
600
1 200
2 400
4 800
9 600
19 200
38 400
EXTAL frequency: 16 MHz
Dec value
Hex value
4545
$11C1
3333
$0D05
1666
$0682
833
$0341
416
$01A0
208
$00D0
104
$0068
52
$0034
26
$001A
13
$000D
7.6.2 SCCR1 — SCI control register 1
Address bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
State
on reset
7
SCI control 1 (SCCR1)
$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
M — Mode (select character format)
1 (set) – Start bit, 9 data bits, 1 stop bit.
0 (clear) – Start bit, 8 data bits, 1 stop bit.
MC68HC11KW1
SERIAL COMMUNICATIONS INTERFACE
7-7