MC68HC908EY16 Datasheet, PDF (128/278 Pages) Motorola, Inc – Microcontrollers

Enhanced Serial Communications Interface (ESCI) Module
13.4.1 Data Format
The SCI uses the standard non-return-to-zero mark/space data format illustrated in Figure 13-3.
PARITY
START
8-BIT DATA FORMAT
(BIT M IN SCC1 CLEAR)
OR DATA
BIT
NEXT
START
BIT _{BIT 0 BIT 1 BIT 2 BIT 3 BIT 4 BIT 5 BIT 6 BIT 7 STOP BIT}
BIT
PARITY
START
9-BIT DATA FORMAT
(BIT M IN SCC1 SET)
OR DATA
BIT
NEXT
START
BIT BIT 0 BIT 1 BIT 2 BIT 3 BIT 4 BIT 5 BIT 6 BIT 7 BIT 8 _STOP BIT
BIT
Figure 13-3. SCI Data Formats
13.4.2 Transmitter
Figure 13-4 shows the structure of the SCI transmitter. The baud rate clock source for the ESCI can be
selected via the configuration bit, ESCIBDSRC.
INTERNAL BUS
÷4
SCP1
SCP0
SCR1
SCR2
SCR0
PRE-
BAUD
SCALER DIVIDER
÷ 16
TXINV
ESCI DATA REGISTER
11-BIT
TRANSMIT
SHIFT REGISTER
H876543210L
SCI_TxD
PDS2
PDS1
PDS0
PSSB4
PSSB3
PSSB2
PSSB1
PSSB0
M
PEN
PARITY
PTY
GENERATION
T8
TRANSMITTER
CONTROL LOGIC
SCTE
SCTE
SCTIE
TC
TCIE
SCTIE
TC
TCIE
Figure 13-4. ESCI Transmitter
SBK
LOOPS
ENSCI
TE
LINT
MC68HC908EY16 • MC68HC908EY8 Data Sheet, Rev. 10
128
Freescale Semiconductor