SERIAL COMMUNICATION INTERFACE (SCI)
6 - 52
PORT C
MOTOROLA
1
234
5
67
8
9
1
0
1
2
9
1
0
1
2
3
4
5
6
78
9
1
0
SBK = 0
SBK = 1
SBK = 1
SBK = 1
SBK = 0
D0
D1
D2
D3
D4
D5
D6
D7
ST
OP
IDLE LINE
ST
•
10 OR 11 ONES/ZEROS WILL BE SENT DEPENDING ON THE WORD LENGTH SPECIFIED BY WDS2, WDS1, WDS0.
1.
WRITE
THE LAST BYTE
T
O STX.
2.
W
AIT FOR
TRDE = 1.
THE LAST BYTE IS NO
W IN
THE
TRANSMIT SHIFT REGISTER.
3.
CLEAR
TE AND SET BA
CK
T
O ONE.
THIS Q
UEUES
THE PREAMBLE
T
O FOLLO
W
THE LAST BYTE.
4.
WRITE
THE FIRST BYTE
T
O FOLLO
W
THE PREAMBLE INT
O SRX.
X:$FFF0
1
5
1
4
1
3
1
2
1
1
1
0
9
8
7
6
5
4
3210
SCKP
TMIE
TIE
RIE
ILIE
TE
RE
W
OMS
R
WU
W
AKE
SBK
SSFTD
WDS2
WDS1
WDS0
SCI INTERF
A
CE CONTR
OL REGISTER (SCR)
(READ/WRITE)
STIR
T
OGGLE (1 - 0 - 1)
T
O SEND A
CHARA
CTER
TIME OF ALL
ONES (MARKS)
T
OGGLE (0 - 1 - 0)
T
O SEND A
CHARA
CTER
TIME OF ALL
ZER
OS (SP
A
CES)
MARKS (ONES)
S
T
0123
4
567
S
T
O
P
S
T
LAST CHARA
CTER
PREAMBLE OF 10 ONES
FIRST CHARA
CTER
SP
A
CES (ZER
OS)
D4
D5
D6
D7
ST
OP
ST
OP
ST
D0
D1
CHARA
CTER ENDS
BEFORE BREAK BEGINS
.
ST
AR
T
OF
BREAK
BREAK PERIOD IS AN EXA
CT MUL
TIPLE OF
CHARA
CTER TIMES
.
ST
AR
T
OF
BREAK
FIRST
CHARA
CTER
AFTER BREAK
A ST
OP BIT A
T
THE END OF
THE BREAK
WILL BE INSER
TED
BEFORE
THE NEXT CHARA
CTER ST
AR
TS
Figure 6-27 Transmitting Marks and Spaces
F
re
e
sc
a
le
S
e
m
ic
o
n
d
u
c
to
r,
I
Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
n
c
.
..