ZiLOG Z8 Series User Manual

Z8
®
CPU
User Manual
UM001604-0108 Instruction Description
161
Add With Carry
Syntax
ADC dst, src
Instruction Format
Operation
dst ← dst + src + C
The source operand, along with the setting of the Carry (C) Flag, is added to the destina-
tion operand. Two’s complement addition is performed. The sum is stored in the destina-
tion operand. The contents of the source operand are not affected. In multiple precision
arithmetic, this instruction permits the carry from the addition of low order operands to be
carried into the addition of high order operands.
Address modes R or IR can be used to specify a 4-bit Working Register. In this format, the
source or destination Working Register operand is specified by adding
1110b (Eh) to the
high nibble of the operand. For example, if Working Register R12 (CH) is the destination
operand, then
ECh is used as the destination operand in the Op Code.
Cycles
OPC
(Hex)
Address
Mode
dst src
OPC dst src
602rr
603rlr
OPC src dst
10 04 R R
10 05 R IR
OPC dst src
10 06 R IM
10 07 IR IM
Flag Description
C Set if there is a carry from the most significant bit of the result; cleared otherwise.
Z Set if the result is zero; cleared otherwise.
S Set if the result is negative; cleared otherwise.
V Set if an arithmetic overflow occurs, that is, if both operands are of the same sign
and the result is of the opposite sign; cleared otherwise.
D Always cleared.
H Set if there is a carry from the most significant bit of the low order four bits of the
result; cleared otherwise.
Note:

ZiLOG Z8 Series Specifications

General

Brand	ZiLOG
Model	Z8 Series
Category	Microcontrollers
Language	English

Summary

Address Space

Z8 CPU Standard Register File

Details the standard register file structure, including I/O, general-purpose, and control registers.

Z8 Expanded Register File (ERF)

Reset

Reset Pin, Internal POR Operation

Explains the function of the RESET pin and internal Power-On Reset for chip initialization.

Watchdog Timer

Watchdog Timer

Describes the retriggerable one-shot timer that resets the CPU if it reaches its terminal count.

Counters and Timers

TIN Modes

Interrupts

Interrupt Sources

Lists interrupt types, sources, and vectors available in the Z8 family processors.

Interrupt Initialization

Power-Down Modes

Halt Mode Operation

Explains HALT mode, suspending execution while keeping the oscillator active.

Stop Mode Operation

Details STOP mode for lowest standby current by turning off internal clocks.

Serial Input/Output

UART Introduction

SPI Operation

Details SPI usage in master and slave modes, including data transfer and chip select.

External Interface

Introduction

External Addressing Configuration

Instruction Set

Processor Flags

Condition Codes

Instruction Description

Provides detailed descriptions of Z8 instructions, including syntax, operation, and flags.