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2 operation in synchronous mode (operation mode 2), Operation in synchronous mode (operation mode 2) – FUJITSU F2MCTM-16LX User Manual

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CHAPTER 20 LIN-UART

20.7.2

Operation in Synchronous Mode (Operation Mode 2)

The clock synchronous transfer method is used for LIN-UART operation mode 2 (normal
mode).

Operation in Synchronous Mode (Operation mode 2)

Transfer data format

In the synchronous mode, 8-bit data is transferred without start or stop bits if the SSM bit of the Extended

Communication Control Register (ECCR) is 0. Also, when the start/stop bit is provided (ECCR: SSM = 1),

presence or absence of the parity bit can be selected (SCR: PEN). The figure below illustrates the data

format during a transmission in the synchronous operation mode.

Figure 20.7-3 Transfer Data Format (operation mode 2)

Clock inversion function

If the SCES bit of the Extended Status/Control Register (ESCR) is set to "1", the serial clock is inverted.

Therefore, in slave mode LIN-UART samples the data bits at the falling edge of the received serial clock.

Note, that in master mode if SCES is set to "1", the clock signal’s mark level is "0".

Figure 20.7-4 Transfer Data Format with Clock Inversion

Start/stop bits

If the SSM bit of the Extended Communication Control Register (ECCR) is set to "1", the data format gets

additional start and stop bits like in asynchronous mode.

*

*

(ECCR:SSM=0,SCR:PEN=0)

(ECCR:SSM=1,SCR:PEN=0)

(ECCR:SSM=1,SCR:PEN=1)

D0

D1 D2 D3 D4

D5

D6 D7

ST D0

D1 D2 D3 D4

D5

D6 D7

ST D0

D1 D2 D3 D4

D5 D6

D7

P

SP

SP

SP

SP

Reception or transfer data

Reception or transfer data

Reception or transfer data

*: Set to 2-stop bits (SCR: SBL = 1)

ST: Start bit SP: Stop bit P: Parity bit LSB first

data frame

Reception or transmission clock

Data stream (SSM = 1)
(here: no parity, 1 stop bit)

ST

SP

(SCES = 0, CCO = 0):

Reception or transmission clock
(SCES = 1, CCO = 0):

mark level

mark level