S9S08SL8F1CTJ Datasheet, PDF (210/356 Pages) Freescale Semiconductor, Inc – provides the functional version of the on-chip modules

PROCESS
VALID ID
N
COMMAND MESSAGE
?
Y
EXTENDED FRAME ^Y
?
N
PROCESS
REQUEST MESSAGE
INITIALIZE SW BYTE COUNT
WRITE SLCDLC FOR THIS ID
0nxx xxxx
(TXGO = 0)
(CHKMOD = n)
WRITE SLCDLC FOR THIS ID
0n00 0xxx
(TXGO = 0)
(CHKMOD = n)
EXIT ISR
PROCESS ERROR CODE:
BYTE FRAMING ERROR
CHECKSUM-ERROR
NO-BUS-ACTIVITY
RECEIVE BUFFER OVERRUN
CLEAR SLCF
EXIT ISR
RETURN TO IDLE
INTERRUPT
READ SLCSV
Y
ERROR CODE
?
N
EMPTY RX BUFFER
CLEAR SLCF
EXIT ISR
INTERRUPT
READ SLCSV
ERROR CODE
Y
?
PROCESS ERROR CODE:
BYTE FRAMING ERROR
NO-BUS-ACTIVITY
RECEIVE BUFFER OVERRUN
CLEAR SLCF
N
1. EMPTY RX BUFFER
2. DECREMENT SW BYTE COUNT BY 8
3. CLEAR SLCF
EXIT ISR
RETURN TO IDLE
N
LAST FRAME
(SW BYTE COUNT <8)
?
Y
Figure 12-15. Handling Command Messages (Data Receive)
The SLIC transmit go (TXGO) bit should be 0 for command frames, indicating to the SLIC that data is
coming from the master. The checksum mode control (CHKMOD) bit allows the user to select which
method of checksum calculation is desired for this message frame. The LIN 1.3 checksum does not include
the identifier byte in the calculation, while the SAE version does include this byte. Because the identifier
is already received by the SLIC by this time, the default is to include it in the calculation. If a LIN 1.3
checksum is desired, a 1 in CHKMOD will reset the checksum circuitry to begin calculating the checksum
MC9S08EL32 Series and MC9S08SL16 Series Data Sheet, Rev. 3
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