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FUJITSU F2MCTM-16LX User Manual

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CHAPTER 20 LIN-UART

Oversampling Circuit

The oversampling circuit oversamples the incoming data at the SINn pin for five times in the asynchronous

mode. The received value is determined by majority decision of sampling time. It is switched off in

synchronous operation mode.

Interrupt Generation Circuit

The interrupt generation circuit administers all cases of generating a reception or transmission interrupt. If a

corresponding interrupt enable bit is set, the interrupt will be generated immediately.

LIN synch Break and Synchronization Field Detection Circuit

The LIN break and LIN synchronization field detection circuit detects a LIN synch break if a LIN master

node is sending a message header. If a LIN synch break is detected LBD flag bit is generated. The first and

the fifth falling edge of the LIN synchronization field is recognized by this circuit by generating an internal

signal for the Input Capture Unit to measure the actual serial clock synchronization of the transmitting

master node.

LIN Synch Break Generation Circuit

The LIN break generation circuit generates a LIN synch break of a determined length.

Bus Idle Detection circuit

The bus idle detection circuit recognizes if neither reception nor transmission is going on. In this case, the

circuit generates the special flag bits TBI and RBI.

LIN-UART Serial Mode Register (SMR)

This register performs the following operations:

Selecting the LIN-UART operation mode

Selecting a clock input source

Selecting if an external clock is connected "one-to-one" or connected to the reload counter

Resetting dedicated reload timer

Resetting the LIN-UART software (preserving the settings of the registers)

Specifying whether to enable serial data output to the corresponding pin

Specifying whether to enable clock output to the corresponding pin