Usage Notes; Usage Notes On Bit Manipulation Instructions; Figure 2.13 State Transitions - Renesas H8S Series Hardware Manual

Exception handling state
Request for
exception
handling
Program execution state
Notes: From any state, a transition to hardware standby mode occurs when STBY goes low.
* From any state except hardware standby mode, a transition to the reset state
occurs whenever RES goes low. A transition can also be made to the reset state
when the watchdog timer overflows.
2.9

Usage Notes

2.9.1

Usage Notes on Bit Manipulation Instructions

The BSET, BCLR, BNOT, BST, and BIST instructions are used to read data in bytes, then, after
bit manipulation, they write data in bytes again. Therefore, special care is necessary to use these
instructions for the registers and the ports that include write-only bit.
The BCLR instruction can be used to clear the flags in the internal I/O registers to 0. In this time,
if it is obvious that the flag has been set to 1 in the interrupt processing routine or other
processing, there is no need to read the flag beforehand.
Reset state
End of
exception
handling
SLEEP instruction

Figure 2.13 State Transitions

*
Bus-released state
Bus
request
Program halt state
Rev. 6.00 Mar 15, 2006 page 49 of 570
Section 2 CPU
End of
bus request
REJ09B0211-0600