MC68HC705JD FREESCALE [Freescale Semiconductor, Inc], MC68HC705JD Datasheet - Page 57

• Manufacturer Part Number: MC68HC705JD
• Description: member of the low-cost
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

10.2.2 Read-Modify-Write Instructions
10.2.3 Jump/Branch Instructions
Rev. 2
These instructions read a memory location or a register, modify its contents, and
write the modified value back to the memory location or to the register. The test for
negative or zero instruction (TST) is an exception to the read-modify-write
sequence because it does not write a replacement value.
read-modify-write instructions.
Jump instructions allow the CPU to interrupt the normal sequence of the program
counter. The unconditional jump instruction (JMP) and the jump to subroutine
instruction (JSR) have no register operand. Branch instructions allow the CPU to
interrupt the normal sequence of the program counter when a test condition is met.
If the test condition is not met, the branch is not performed. All branch instructions
use relative addressing.
Bit test and branch instructions cause a branch based on the state of any readable
bit in the first 256 memory locations. These three-byte instructions use a
combination of direct addressing and relative addressing. The direct address of the
byte to be tested is in the byte following the opcode. The third byte is the signed
offset byte. The CPU finds the conditional branch destination by adding the third
byte to the program counter if the specified bit tests true. The bit to be tested and
Freescale Semiconductor, Inc.
Arithmetic Shift Left
Arithmetic Shift Right
Clear Bit in Memory
Set Bit in Memory
Clear
Complement (One’s Complement)
Decrement
Increment
Logical Shift Left
Logical Shift Right
Negate (Two’s Complement)
Rotate Left through Carry Bit
Rotate Right through Carry Bit
Test for Negative or Zero
Table 10-2. Read-Modify-Write Instructions
For More Information On This Product,
Go to: www.freescale.com
INSTRUCTION SET
Instruction
Mnemonic
BCLR
BSET
COM
NEG
ROR
ASR
CLR
DEC
ROL
ASL
LSR
TST
INC
LSL
Table 10-2
lists the
10-5
10
11
12
13
14
15
16
17
18
19
20
1
2
3
4
5
6
7
8
9