ATtiny2313 Atmel Corporation, ATtiny2313 Datasheet - Page 26

• Manufacturer Part Number: ATtiny2313
• Manufacturer: Atmel Corporation

Specifications of ATtiny2313

• Flash (kbytes): 2 Kbytes
• Pin Count: 20
• Max. Operating Frequency: 20 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 4
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 18
• Ext Interrupts: 18
• Usb Speed: No
• Usb Interface: No
• Spi: 2
• Twi (i2c): 1
• Uart: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• 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: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.8 to 5.5
• Operating Voltage (vcc): 1.8 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 2
• Output Compare Channels: 4
• Input Capture Channels: 1
• Pwm Channels: 4
• 32khz Rtc: No
• Calibrated Rc Oscillator: Yes

Oscillator Calibration
Register – OSCCAL
26
ATtiny2313
When this Oscillator is selected, start-up times are determined by the SUT Fuses as shown in
Table
Table 7. Start-up times for the internal calibrated RC Oscillator clock selection
Note:
• Bits 6..0 – CAL6..0: Oscillator Calibration Value
Writing the calibration byte to this address will trim the internal Oscillator to remove process vari-
ations from the Oscillator frequency. This is done automatically during Chip Reset. When
OSCCAL is zero, the lowest available frequency is chosen. Writing non-zero values to this regis-
ter will increase the frequency of the internal Oscillator. Writing 0x7F to the register gives the
highest available frequency. The calibrated Oscillator is used to time EEPROM and Flash
access. If EEPROM or Flash is written, do not calibrate to more than 10% above the nominal fre-
quency. Otherwise, the EEPROM or Flash write may fail. Note that the Oscillator is intended for
calibration to 8.0/4.0 MHz. Tuning to other values is not guaranteed, as indicated in
Avoid changing the calibration value in large steps when calibrating the Calibrated Internal RC
Oscillator to ensure stable operation of the MCU. A variation in frequency of more than 2% from
one cycle to the next can lead to unpredictable behavior. Changes in OSCCAL should not
exceed 0x20 for each calibration.
Table 8. Internal RC Oscillator Frequency Range.
Bit
Read/Write
Initial Value
SUT1..0
OSCCAL Value
10
00
01
11
(1)
7.
0x3F
0x7F
0x00
1. The device is shipped with this option selected.
Start-up Time from Power-
down and Power-save
R
7
–
Min Frequency in Percentage of
6 CK
6 CK
6 CK
CAL6
R/W
6
Nominal Frequency
CAL5
R/W
100%
5
50%
75%
Device Specific Calibration Value
CAL4
R/W
4
Additional Delay from
Reset (V
Reserved
14CK + 4.1 ms
14CK + 65 ms
CAL3
R/W
3
14CK
CC
= 5.0V)
Max Frequency in Percentage of
CAL2
R/W
2
Nominal Frequency
CAL1
R/W
Recommended Usage
BOD enabled
Fast rising power
Slowly rising power
1
100%
150%
200%
CAL0
R/W
0
OSCCAL
2543L–AVR–08/10
Table
8.