ATtiny26 Atmel Corporation, ATtiny26 Datasheet - Page 10

• Manufacturer Part Number: ATtiny26
• Manufacturer: Atmel Corporation

Specifications of ATtiny26

• Flash (kbytes): 2 Kbytes
• Pin Count: 20
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 16
• Ext Interrupts: 11
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Twi (i2c): 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 11
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 0.12
• Eeprom (bytes): 128
• Self Program Memory: NO
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 2.7 to 5.5
• Operating Voltage (vcc): 2.7 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 2
• Output Compare Channels: 3
• Pwm Channels: 4
• 32khz Rtc: No
• Calibrated Rc Oscillator: Yes

Status Register –
SREG
10
ATtiny26(L)
The AVR Status Register – SREG – at I/O space location $3F is defined as:
• Bit 7 – I: Global Interrupt Enable
The Global Interrupt Enable bit must be set (one) for the interrupts to be enabled. The individual
interrupt enable control is then performed in the Interrupt Mask Registers – GIMSK and TIMSK.
If the Global Interrupt Enable Register is cleared (zero), none of the interrupts are enabled inde-
pendent of the GIMSK and TIMSK values. The I-bit is cleared by hardware after an interrupt has
occurred, and is set by the RETI instruction to enable subsequent interrupts. The I-bit can also
be set and cleared by the application with the SEI and CLI instructions, as described in the
instruction set reference.
• Bit 6 – T: Bit Copy Storage
The Bit Copy instructions BLD (Bit LoaD) and BST (Bit STore) use the T-bit as source and desti-
nation for the operated bit. A bit from a register in the Register File can be copied into T by the
BST instruction, and a bit in T can be copied into a bit in a register in the Register File by the
BLD instruction.
• Bit 5 – H: Half Carry Flag
The Half Carry Flag H indicates a Half Carry in some arithmetic operations. See the Instruction
Set Description for detailed information.
• Bit 4 – S: Sign Bit, S = N ⊕ V
The S-bit is always an exclusive or between the Negative Flag N and the Two’s Complement
Overflow Flag V. See the Instruction Set Description for detailed information.
• Bit 3 – V: Two’s Complement Overflow Flag
The Two’s Complement Overflow Flag V supports two’s complement arithmetics. See the
Instruction Set Description for detailed information.
• Bit 2 – N: Negative Flag
The Negative Flag N indicates a negative result after the different arithmetic and logic opera-
tions. See the Instruction Set Description for detailed information.
• Bit 1 – Z: Zero Flag
The Zero Flag Z indicates a zero result after the different arithmetic and logic operations. See
the Instruction Set Description for detailed information.
• Bit 0 – C: Carry Flag
The Carry Flag C indicates a carry in an arithmetic or logic operation. See the Instruction Set
Description for detailed information.
Bit
$3F ($5F)
Read/Write
Initial Value
R/W
7
0
I
R/W
T
6
0
R/W
5
H
0
R/W
4
S
0
R/W
3
V
0
R/W
N
2
0
R/W
1
Z
0
R/W
C
0
0
SREG
1477K–AVR–08/10