Datasheet

Section 2 CPU
Page 82 of 1384 R01UH0310EJ0500 Rev. 5.00
Sep 25, 2012
H8S/2426, H8S/2426R, H8S/2424 Group
2.9 Usage Note
2.9.1 Usage Notes on Bit-wise Operation Instructions
The BSET, BCLR, BNOT, BST, and BIST instructions are used to read data in byte-wise, operate
the data in bit-wise, and write the result of the bit-wise operation in bit-wise 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 handler, there is no need to read the
flag beforehand.