Freescale Semiconductor MC68HC908MR32 Manual Do Utilizador
Serial Communications Interface Module (SCI)
MC68HC908MR32 • MC68HC908MR16 Data Sheet, Rev. 6.1
164
Freescale Semiconductor
Figure 13-6. SCI Receiver Block Diagram
13.3.3.1 Character Length
The receiver can accommodate either 8-bit or 9-bit data. The state of the M bit in SCI control register 1
(SCC1) determines character length. When receiving 9-bit data, bit R8 in SCI control register 2 (SCC2)
is the ninth bit (bit 8). When receiving 8-bit data, bit R8 is a copy of the eighth bit (bit 7).
(SCC1) determines character length. When receiving 9-bit data, bit R8 in SCI control register 2 (SCC2)
is the ninth bit (bit 8). When receiving 8-bit data, bit R8 is a copy of the eighth bit (bit 7).
ALL 1s
ALL 0s
M
WAKE
ILTY
PEN
PTY
BKF
RPF
H
8
7
6
5
4
3
2
1
0
L
11-BIT
RECEIVE SHIFT REGISTER
ST
OP
ST
ART
DATA
RECOVERY
OR
ORIE
NF
NEIE
FE
FEIE
PE
PEIE
SCRIE
SCRF
ILIE
IDLE
WAKEUP
LOGIC
PARITY
CHECKING
MSB
ERROR CPU INTERRUPT
REQU
EST
CPU INTERRUPT
REQU
EST
SCI DATA REGISTER
R8
ORIE
NEIE
FEIE
PEIE
SCRIE
ILIE
RWU
SCRF
IDLE
OR
NF
FE
PE
PTF4/RxD
INTERNAL BUS
PRE-
SCALER
BAUD
DIVIDER
÷ 4
÷ 16
SCP1
SCP0
SCR1
SCR2
SCR0
f
OP