AN2503 Freescale Semiconductor / Motorola, AN2503 Datasheet - Page 13

• Manufacturer Part Number: AN2503
• Description: Slave LIN Driver for the MC68HC908QT/QY Family
• Manufacturer: Freescale Semiconductor / Motorola

GetChar() Function
MOTOROLA
After the byte is received, the GetChar() function handles the byte in one of two
ways, depending the byte type.
This process can be seen in
Slave LIN Driver for the MC68HC908QT/QY Family
•
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Freescale Semiconductor, Inc.
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Byte received is an ID — These steps must be performed:
1. The parity error is checked based on a mixed-parity algorithm
2. The ID is validated based on a ROM table and using FindInTable()
3. If the ID is defined, the length and direction (transmission or
Byte received is data — A previously received ID defined the direction
as reception, and data is received by following these steps:
1. Save the data received in the predetermined buffer
2. If the buffer was received (based on the defined length), the
3. If the checksum is correct, the buffer is tested to determine if byte is
4. If it is a SleepMode command, the MCU enters low
5. If it is a normal frame, the MCU will wait for the next frame.
function
reception) is obtained
checksum is calculated using CalcCheckSum() function
a SleepMode command.
power-consumption mode.
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Figure
9.
Driver Functionality
AN2503/D
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