Chapter 20 Serial Communication Interface (S12SCIV5)
MC9S12XE-Family Reference Manual , Rev. 1.19
738
Freescale Semiconductor
Figure 20-14. Detailed SCI Block Diagram
20.4.1
Infrared Interface Submodule
This module provides the capability of transmitting narrow pulses to an IR LED and receiving narrow
pulses and transforming them to serial bits, which are sent to the SCI. The IrDA physical layer
specification defines a half-duplex infrared communication link for exchange data. The full standard
includes data rates up to 16 Mbits/s. This design covers only data rates between 2.4 Kbits/s and 115.2
Kbits/s.
The infrared submodule consists of two major blocks: the transmit encoder and the receive decoder. The
SCI transmits serial bits of data which are encoded by the infrared submodule to transmit a narrow pulse
SCI Data
Receive
Shift Register
SCI Data
Register
Transmit
Shift Register
Register
Baud Rate
Generator
SBR12:SBR0
Bus
Transmit
Control
÷
16
Receive
and Wakeup
Data Format
Control
Control
T8
PF
FE
NF
RDRF
IDLE
TIE
OR
TCIE
TDRE
TC
R8
RAF
LOOPS
RWU
RE
PE
ILT
PT
WAKE
M
Clock
ILIE
RIE
RXD
RSRC
SBK
LOOPS
TE
RSRC
IREN
R16XCLK
Ir_RXD
TXD
Ir_TXD
R16XCLK
R32XCLK
TNP[1:0]
IREN
Transmit
Encoder
Receive
Decoder
SCRXD
SCTXD
Infrared
Infrared
TC
TDRE
RDRF/OR
IDLE
Active Edge
Detect
Break Detect
RXD
BKDFE
BERRM[1:0]
BKDIE
BKDIF
RXEDGIE
RXEDGIF
BERRIE
BERRIF
SCI
Interrupt
Request
LIN Transmit
Collision
Detect
Because
of
an
order
from
the
United
States
International
Trade
Commission,
BGA-packaged
product
lines
and
part
numbers
indicated
here
currently
are
not
available
from
Freescale
for
import
or
sale
in
the
United
States
prior
to
September
2010:
S12XE
products
in
208
MAPBGA
packages