HC05 datasheet(152/232 Pages) MOTOROLA

152 / 232 page

MOTOROLA

11-4

MC68HC05X16

Rev. 1

CPU CORE AND INSTRUCTION SET

11.2.1

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 11-2 for a complete list of register/memory instructions.

11.2.2

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 11-3.

11.2.3

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

11.2.4

Read/modify/write instructions

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 11-5 for a complete list of read/modify/write instructions.

11.2.5

Control instructions

These instructions are register reference instructions and are used to control processor operation

during program execution. Refer to Table 11-6 for a complete list of control instructions.

11.2.6

Tables

Tables for all the instruction types listed above follow. In addition there is a complete alphabetical

listing of all the instructions (see Table 11-7), and an opcode map for the instruction set of the

M68HC05 MCU family (see Table 11-8).

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HC05 Datasheet(PDF) 152 Page - Motorola, Inc