S9S08SL8F1CTJ Datasheet, PDF (250/356 Pages) Freescale Semiconductor, Inc – provides the functional version of the on-chip modules

Serial Communications Interface (S08SCIV4)
14.1.3 Block Diagram
Figure 14-2 shows the transmitter portion of the SCI.
INTERNAL BUS
(WRITE-ONLY)
SCID – Tx BUFFER
11-BIT TRANSMIT SHIFT REGISTER
M
LOOPS
RSRC
LOOP
CONTROL
1 × BAUD
RATE CLOCK
H876543210L
SHIFT DIRECTION
TXINV
TO RECEIVE
DATA IN
TO TxD PIN
T8
PE
PARITY
PT
GENERATION
TE
SBK
TXDIR
BRK13
TRANSMIT CONTROL
SCI CONTROLS TxD
TxD DIRECTION
TO TxD
PIN LOGIC
TDRE
TIE
TC
TCIE
Figure 14-2. SCI Transmitter Block Diagram
Tx INTERRUPT
REQUEST
MC9S08EL32 Series and MC9S08SL16 Series Data Sheet, Rev. 3
252
Freescale Semiconductor