SH7052 datasheet(566/919 Pages) RENESAS

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Initialization (after Hardware Reset Only): These settings should be made while the HCAN is

in bit configuration mode.

1. IRR0 clearing

The reset interrupt flag (IRR0) is always set after a power-on reset or recovery from software

standby mode. As an HCAN interrupt is initiated immediately when interrupts are enabled,

IRR0 should be cleared.

2. HCAN pin port settings

To prevent erroneous identification of CAN bus data, HCAN pin port settings should be made

first. See section 15.3.2, HCAN Pin Port Settings, and section 18, Pin Function Controller, for

details.

3. Bit rate settings

Set values relating to the CAN bus communication speed and re-synchronization. See section

15.3.2, Bit Rate Settings, for details.

4. Mailbox transmit/receive settings

Mailbox transmit/receive settings should be made in advance. A total of 30 mailbox can be set

for transmission or reception (mailboxes 1 to 15 in HCAN0 and HCAN1). To set a mailbox for

transmission, clear the corresponding bit to 0 in the mailbox configuration register (MBCR).

See section 15.3.2, Mailbox Transmit/Receive Settings, for details.

5. Mailbox initialization

As message control/data registers (MCx[x], MDx[x]) are configured in RAM, their initial

values after powering on are undefined, and so bit initialization is necessary. Write 0s or 1s to

the mailboxes. See section 15.3.2, Mailbox Transmit/Receive Settings, for details.

6. Message transmission method setting

Set the transmission method for mailboxes designated for transmission. The following two

transmission methods can be used. See section 15.3.2, Setting the Message Transmission

Method, for details.

a. Transmission order determined by message identifier priority

b. Transmission order determined by mailbox number priority

SH7052 Datasheet(PDF) 566 Page - Renesas Technology Corp