Z8F082AHH020SG2156 Zilog, Z8F082AHH020SG2156 Datasheet - Page 15

• Manufacturer Part Number: Z8F082AHH020SG2156
• Description: IC ENCORE XP MCU FLASH 8K
• Manufacturer: Zilog
• Series: Encore!® XP®r

Specifications of Z8F082AHH020SG2156

• Core Processor: Z8
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: IrDA, UART/USART
• Peripherals: Brown-out Detect/Reset, LED, LVD, POR, PWM, Temp Sensor, WDT
• Number Of I /o: 17
• Program Memory Size: 8KB (8K x 8)
• Program Memory Type: FLASH
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 3.6 V
• Data Converters: A/D 7x10b
• Oscillator Type: Internal
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 20-SSOP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Other names: Q5278375

UM012811-0904
Figure 2. Flags Register
Interrupts, the Software Trap (TRAP) instruction, and Illegal Instruction Traps all write
the value of the Flags Register to the stack. Executing an Interrupt Return (IRET) instruc-
tion restores the value saved on the stack into the Flags Register.
Carry Flag
The Carry flag (C) is 1 when the result of an arithmetic operation generates a carry out of
or a borrow into the most significant bit (Bit 7) of the data. Otherwise, the Carry flag is 0.
Some bit rotate or shift instructions also affect the Carry flag. There are three instructions
available for directly changing the value of the Carry Flag:
•
•
•
Zero Flag
For arithmetic and logical operations, the Zero (Z) flag is 1 if the result is 0. Otherwise, the
Zero flag is 0. If the result of testing bits in a register is
the Zero flag is 0. Also, if the result of a rotate or shift operation is
otherwise, the Zero flag is 0.
Sign Flag
The Sign (S) flag stores the value of the most-significant bit of a result following an arith-
metic, logical, rotate or shift operation. For signed numbers, the eZ8 CPU uses binary
two’s complement to represent the data and perform the arithmetic operations. A 0 in the
Complement Carry Flag (CCF)
Reset Carry Flag (RCF)
Set Carry Flag (SCF)
Bit
C Z S V D H F2 F1 Flags Register
7
Bit
0
User Flags
Half Carry Flag
Decimal Adjust Flag
Overflow Flag
Sign Flag
Zero Flag
Carry Flag
00H
, the Zero flag is 1; otherwise,
00H
Architectural Overview
, the Zero flag is 1;
User Manual
eZ8 CPU
5