MC68HC705C Motorola, MC68HC705C Datasheet - Page 155

• Manufacturer Part Number: MC68HC705C
• Description: HCMOS Microcontroller Unit
• Manufacturer: Motorola

12.3.8 Relative
12.4 Instruction Types
MC68HC705C8A — Rev. 2.0
MOTOROLA
Relative addressing is only for branch instructions. If the branch
condition is true, the CPU finds the effective branch destination by
adding the signed byte following the opcode to the contents of the
program counter. If the branch condition is not true, the CPU goes to the
next instruction. The offset is a signed, two’s complement byte that gives
a branching range of –128 to +127 bytes from the address of the next
location after the branch instruction.
When using the Motorola assembler, the programmer does not need to
calculate the offset, because the assembler determines the proper offset
and verifies that it is within the span of the branch.
The MCU instructions fall into five categories:
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•
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Register/memory instructions
Read-modify-write instructions
Jump/branch instructions
Bit manipulation instructions
Control instructions
Instruction Set
Instruction Types
Technical Data
Instruction Set
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