HCSInstructionset.pptVIP

HCS12 Instruction set INSTRUCTION SET DATA HANDLING INSTRUCTIONS(DATA MOVEMENT) STACK OPERATION DATA HANDLING INSTRUCTIONS(TRANSFER AND EXCHANGE) DATA HANDLING INSTRUCTIONS(ALTER DATA) DATA HANDLING INSTRUCTIONS(ALTER DATA) DATA HANDLING INSTRUCTIONS DATA HANDLING INSTRUCTIONS DATA HANDLING INSTRUCTIONS(SHIFT AND ROTATE) DATA TEST INSTRUCTIONS CONDITIONAL BRANCH INSTRUCTIONS (1 0F 3) BRANCH IF BITS SET OR CLEAR (3 of 3) ARITHMETIC INSTRUCTIONS (4 of 4)FRACTIONAL DIVIDE INSTRUCTION ARITHMETIC INSTRUCTIONS (1 of 4) ARITHMETIC INSTRUCTIONS (2 of 4) ARITHMETIC INSTRUCTIONS (3 of 4)DIVIDE INSTRUCTIONS EXTENDED MULTIPLY AND ACCUMULATE(EMACS) LOGIC INSTRUCTIONS JUMP AND BRANCH INSTRUCTIONS CONDITION CODE REGISTER INSTRUCTIONS BLOCK MOVE ROUTINE CLEAR RAM ROUTINE INTRODUCE ADD DECIMAL ADJUST INSTRUCTIONS: ABY - This is one of the rare places the Motorola instruction set isn’t entirely general. You can add B to X or Y but you can’t add A to X or Y. ABY is useful for calculating offsetts into multi-dimensional arrays. If you want to do 16-bit arithmetic on X or Y just do XGDX then 16-bit arithmetic such as ADDD, then XGDX again. Note X acts as temp for D in this seq. ABA ADDs(A,B,D) affect N,Z,C,V ABX ABY (add ACCB to index register) does not affect CCR ABX ABY are useful for pointing index register to new (calculated) address (add ACCA to index register is not available) ADDC uses previous carry value as add-in carry in current addition DAA is only of use immediately AFTER executing ADDA, to transform the accumulator’s hexadecimal results to decimal using the Half carry bit. INTRODUCE: SUBTRACT MULTIPLY INSTRUCTIONS Instructions on slide are all register ops SBA SUBs (A,B,D) affect N,Z,V,C SUBC uses previous carry value as a borrow in current subtraction MUL is 8x8 unsigned multiply giving a 16-bit result MUL takes 10 clocks affects C bit according to bit 7 (ACCB bit 7) of 16-bit result QUESTION: WHAT DOES THE C BIT REPRESENT IN SUBTRACTION: -two DIV instr