Atmel Evaluation Kit AT91SAM9M10-G45-EK AT91SAM9M10-G45-EK Data Sheet

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SAM9M10 [DATASHEET]

6355F–ATARM–12-Mar-13

In this configuration, the PDC transfers only the DATA. The Identifier must be read by the user in the LIN Identifier
register (US_LINIR). The LIN mode must be written by the user in the LIN Mode register (US_LINMR).

The WRITE buffer contains the DATA if the USART sends the response (NACT=PUBLISH).

The READ buffer contains the DATA if the USART receives the response (NACT=SUBSCRIBE).

Slave Node with PDC

Any node in a sleeping LIN cluster may request a wake-up.

In the LIN 2.0 specification, the wakeup request is issued by forcing the bus to the dominant state from 250 μs to 5
ms. For this, it is necessary to send the character 0xF0 in order to impose 5 successive dominant bits. Whatever
the baud rate is, this character respects the specified timings.

• Baud rate min = 1 kbit/s -> Tbit = 1ms -> 5 Tbits = 5 ms

• Baud rate max = 20 kbit/s -> Tbi t= 50 μs -> 5 Tbits = 250 μs

In the LIN 1.3 specification, the wakeup request should be generated with the character 0x80 in order to impose 8
successive dominant bits.

The user can choose by the WKUPTYP bit in the LIN Mode register (US_LINMR) either to send a LIN 2.0 wakeup
request (WKUPTYP=0) or to send a LIN 1.3 wakeup request (WKUPTYP=1).

A wake-up request is transmitted by writing the Control Register (US_CR) with the LINWKUP bit at 1. Once the
transfer is completed, the LINTC flag is asserted in the Status Register (US_SR). It is cleared by writing the Control
Register (US_CR) with the RSTSTA bit at 1.

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DATA 0

DATA N

PDC

(DMA)

RXRDY

USART3

LIN CONTROLLER

APB bus

READ BUFFER

NACT = SUBSCRIBE

DATA 0

DATA N

PDC

(DMA)

TXRDY

USART3

LIN CONTROLLER

APB bus

WRITE BUFFER