39
2513L–AVR–03/2013
ATmega162/V
Time-out. For more information on the pre-programmed calibration value, see the section
“Cali-Note:
1. The device is shipped with this option selected.
When this Oscillator is selected, start-up times are determined by the SUT Fuses as shown in
Table 12. XTAL1 and XTAL2 should be left unconnected (NC).
Note:
1. The device is shipped with this option selected.
Oscillator Calibration
Register – OSCCAL
Bit 7 – Res: Reserved Bit
This bit is reserved bit in the ATmega162, and will always read as zero.
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.
Table 11. Internal Calibrated RC Oscillator Operating Modes
CKSEL3:0
Nominal Frequency
8.0 MHz
Table 12. Start-up Times for the Internal Calibrated RC Oscillator Clock Selection
SUT1:0
Start-up Time from Power-
down and Power-save
Additional Delay from
Reset (VCC = 5.0V)
Recommended Usage
00
6 CK
–
BOD enabled
01
6 CK
4.1 ms
Fast rising power
6 CK
65 ms
Slowly rising power
11
Reserved
Bit
765
4321
0
–
CAL6
CAL5
CAL4
CAL3
CAL2
CAL1
CAL0
OSCCAL
Read/Write
R
R/W
Initial Value
0
Device Specific Calibration Value