HD6473258CP10 Datasheet, PDF (53/301 Pages) Renesas Technology Corp – Hitachi Single-Chip Microcomputer

Table 3-6. Bit-Manipulation Instructions (2)
Instruction
BIXOR
BLD
BILD
BST
BIST
Size*
B
B
B
Function
C ⊕ ¬ [(<bit-No.> of <EAd>)] → C
XORs the C flag with the inverse of a specified bit in a general register
or memory.
The bit number is specified by 3-bit immediate data.
(<bit-No.> of <EAd>) → C
Copies a specified bit in a general register or memory to the C flag.
¬ (<bit-No.> of <EAd>) → C
Copies the inverse of a specified bit in a general register or memory to
the C flag.
The bit number is specified by 3-bit immediate data.
C → (<bit-No.> of <EAd>)
Copies the C flag to a specified bit in a general register or memory.
¬ C → (<bit-No.> of <EAd>)
Copies the inverse of the C flag to a specified bit in a general register or
memory.
The bit number is specified by 3-bit immediate data.
* Size: operand size
B: Byte
Notes on Bit Manipulation Instructions: BSET, BCLR, BNOT, BST, and BIST are read-modify-
write instructions. They read a byte of data, modify one bit in the byte, then write the byte back.
Care is required when these instructions are applied to registers with write-only bits and to the I/O
port registers.
Read
Modify
Write
Read one data byte at the specified address
Modify one bit in the data byte
Write the modified data byte back to the specified address
Example 1: BCLR is executed to clear bit 0 in the port 4 data direction register (P4DDR) under
the following conditions.
P47:
Input pin, Low, MOS pull-up transistor on
P46:
Input pin, High, MOS pull-up transistor off
P45 – P40: Output pins, Low
The intended purpose of this BCLR instruction is to switch P40 from output to input.
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