MC68HC05B4 Datasheet, PDF (120/298 Pages) Motorola, Inc – High-density Complementary Metal Oxide Semiconductor (HCMOS) Microcomputer Unit

10.2.1 Register/memory Instructions
Most of these instructions use two operands. The first operand is either the accumulator or the
index register. The second operand is obtained from memory using one of the addressing modes.
The jump unconditional (JMP) and jump to subroutine (JSR) instructions have no register operand.
Refer to Table 10-2 for a complete list of register/memory instructions.
10.2.2 Branch instructions
These instructions cause the program to branch if a particular condition is met; otherwise, no
operation is performed. Branch instructions are two-byte instructions. Refer to Table 10-3.
10.2.3 Bit manipulation instructions
The MCU can set or clear any writable bit that resides in the first 256 bytes of the memory space
(page 0). All port data and data direction registers, timer and serial interface registers,
control/status registers and a portion of the on-chip RAM reside in page 0. An additional feature
allows the software to test and branch on the state of any bit within these locations. The bit set, bit
clear, bit test and branch functions are all implemented with single instructions. For the test and
branch instructions, the value of the bit tested is also placed in the carry bit of the condition code
register. Refer to Table 10-4.
10.2.4 Read/modify/write instructions
10
These instructions read a memory location or a register, modify or test its contents, and write the
modified value back to memory or to the register. The test for negative or zero (TST) instruction is
an exception to this sequence of reading, modifying and writing, since it does not modify the value.
Refer to Table 10-5 for a complete list of read/modify/write instructions.
10.2.5 Control instructions
These instructions are register reference instructions and are used to control processor operation
during program execution. Refer to Table 10-6 for a complete list of control instructions.
10.2.6 Tables
Tables for all the instruction types listed above follow. In addition there is a complete alphabetical
listing of all the instructions (see Table 10-7 and Table 10-8), and an opcode map for the instruction
set of the M68HC05 MCU family (see Table 10-9).
MOTOROLA
10-4
CPU CORE AND INSTRUCTION SET
TPG
MC68HC05B6
Rev. 4