68HC05 Instruction Set — Part 3
Decrement & Increment Memory & Registers
INC increment a memory location by one INCA increment the accumulator by one INCX increment the index register by one DEC decrement a memory location by one DECA decrement the accumulator by one DECX decrement the index register by one
AND logical AND of the accumulator and an operand ORA inclusive OR of the accumulator and an operand EOR exclusive OR of the accumulator and an operand COM take the one’s complement of (invert) a memory location COMA take the one’s complement of (invert) the accumulator COMX take the one’s complement of (invert) the index register
Notes:
In addition to the ADD/ADC and SUB/SBC instructions, the 68HC05 has dedicated increment and decrement instructions to add one to or subtract one from a memory location, the accumulator, or the index register.
The AND, ORA, and EOR instructions, respectively, take the logical AND, inclusive OR, and exclusive OR of the accumulator and an operand and store the result in the accumulator.
COM, COMA, and COMX take the one’s complement of a memory location, the accumulator, or the index register. The one’s complement of a number is simply the binary inversion of its bits.