h8s-2649 Renesas Electronics Corporation., h8s-2649 Datasheet - Page 509

• Manufacturer Part Number: h8s-2649
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2600 Series
• Manufacturer: Renesas Electronics Corporation.

14.8
14.8.1
HCAN operation can be disabled or enabled using the module stop control register. The HCAN
operation is set to be halted initially. Register access is enabled by clearing module stop mode. For
details, see section 21, Power-Down Modes.
14.8.2
The HCAN is reset by a power-on reset, in hardware standby mode, in software standby mode,
and in module stop mode. All the registers are initialized by a reset, however mailboxes (message
control (MCx[x])/message data (MDx[x])) are not initialized. Mailboxes (message control
(MCx[x])/message data (MDx[x])) are initialized after power-on and at this time, their initial
values are undefined. Therefore, always initialize mailboxes after a power-on reset, a transition to
hardware standby mode, software standby mode, module stop mode, or watch mode. After a
power-on reset, recovery from software standby mode, or cancellation of module stop mode, the
reset interrupt flag (IRR0) is automatically set. Since this bit cannot be masked in the interrupt
mask register (IMR), an HCAN interrupt will be initiated immediately after an HCAN interrupt is
enabled by the interrupt controller without clearing the flag. IRR0 should therefore be cleared at
initialization.
14.8.3
The bus operation interrupt flag (IRR12) in the interrupt register (IRR) is set by CAN bus
operation in HCAN sleep mode. Therefore, this flag is not used by the HCAN to indicate sleep
mode release. Note that the reset status bit (GSR3) in the general status register (GSR) is set even
in sleep mode.
14.8.4
When the mailbox interrupt mask register (MBIMR) is set, the interrupt registers (IRR8, 2, 1) are
not set by reception completion, transmission completion, or transmission cancellation of the set
mailboxes.
Usage Notes
Module Stop Mode Setting
Reset
HCAN Sleep Mode
Interrupts
Section 14 Controller Area Network (HCAN)
Rev. 2.00 Dec. 05, 2005 Page 471 of 724
REJ09B0200-0200