AN2103 Freescale Semiconductor / Motorola, AN2103 Datasheet - Page 33

• Manufacturer Part Number: AN2103
• Description: Local Interconnect Network (LIN) Demonstration
• Manufacturer: Freescale Semiconductor / Motorola

AN2103
MOTOROLA
4.3 Slave Code
description
Port
SCI
SCIRx
SCITx
Drivers
LIN
Figure 17 Slave code data flow diagram
Freescale Semiconductor, Inc.
The slave code is entirely message driven. The software for each
node is practically identical, the only difference being the messages
the node is configured to recognize and the nodeID.
The individual slaves are configured to react to 3 preprogrammed
message identifiers: a NodeX_Write, a NodeX_Read and a common
broadcast message (NodeX_Write message that every slave is
programmed to receive). See
monitors every header that the master drives on the bus, but only
reacts to its configured identifiers. If a NodeX_Write message is
detected, it receives the message data, decodes the command, and
either writes to its LED output port or the external output LED or
enters SLEEP mode. If a NodeX_Read message is detected, the
slave automatically transmits its status information bytes (i.e. Its ID
and the HEX switch settings) on to the LIN bus.
Received messages are handled in exactly the same way as the
master code handles CAN messages. When a new LIN message is
received (NodeX_Write) the code calls a MsgHandlerTable (array of
pointers to functions) and jumps to the appropriate
MsgHandlerFunction.
For More Information On This Product,
GetMsg
Go to: www.freescale.com
PutMsg
Status
Msg
Golbal Data
Message
C omandData
Status
Buffer
Read
Periodic
Table 1
Read
Data
LED
Port Data
MsgIndex
Read
for details. Each slave
Message
Handler
PortD
Slave Code description
Software Description
Port Data
Port Data
Write
Write
PortB
PortE
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