SH7052 Datasheet, PDF (566/919 Pages) Renesas Technology Corp – SuperHTM RISC engine

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
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