SERIAL COMMUNICATION INTERFACE (SCI)
MOTOROLA
PORT C
6 - 69
1
0
X:$FFF2
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
TCM
SCP
COD
CD11
CD10
CD9
CD8
CD7
CD6
CD5
CD4
CD3
CD2
CD1
CD0
RCM
SCI CONTROL REGISTER (SCCR)
(READ/WRITE)
SCLK
SCI TIMER
P:$001C
INTERRUPT
VECTOR
TABLE
DIVIDE
BY 2
PRESCALER
IF SCP = 1, THEN DIVIDE BY 8
IF SCP = 0, THEN DIVIDE BY 1
DIVIDE BY 1
TO 4096
DIVIDE
BY 2
f
osc
X:$FFF0
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
0
1
TIE
RIE
ILIE
TE
RE
WOMS
RWU
WAKE
SBK
0
WDS2 WDS1 WDS0
0
OUTPUT DIVIDER
IF SYNC, THEN DIVIDE BY 2
IF ASYNC THEN:
COD = 1, DIVIDE BY 1
COD = 0, DIVIDE BY 16
TRANSMIT CONTROL
IF ASYNC, THEN DIVIDE BY 16
IF SYNC THEN:
MASTER, DIVIDE BY 2
SLAVE, DIVIDE BY 1
RECEIVE CONTROL
IF ASYNC, THEN DIVIDE BY 16
IF SYNC THEN:
MASTER, DIVIDE BY 2
SLAVE, DIVIDE BY 1
PERIODIC TIMER
DIVIDE BY 16
COD
RCM
TCM
SCKP
SCKP
TCM
TRANSMIT CLOCK
RECEIVE CLOCK
E
X
T
E
R
N
A
L
C
L
O
C
K
I
N
T
E
R
N
A
L
C
L
O
C
K
1
0
SCI CONTROL REGISTER (SCR)
(READ/WRITE)
TMIE
1. WHEN PERIODIC TIMEOUT OCCURS AND TMIE = 1 IN SCR, THEN AN SCI TIMER EXCEPTION IS TAKEN.
SCI TIMER
INTERRUPT
SERVICE
ROUTINE
(FAST OR LONG)
2. PENDING TIMER INTERRUPT IS AUTOMATICALLY CLEARED WHEN INTERRUPT IS SERVICED.
Figure 6-35 SCI Timer Operation
STIR
SCKP
SSFTD
F
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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