ATMEGA324P-15AZ Atmel, ATMEGA324P-15AZ Datasheet - Page 40
ATMEGA324P-15AZ
Manufacturer Part Number
ATMEGA324P-15AZ
Description
MCU AVR 32K FLASH 15MHZ 44-TQFP
Manufacturer
Atmel
Series
AVR® ATmegar
Specifications of ATMEGA324P-15AZ
Core Processor
AVR
Core Size
8-Bit
Speed
16MHz
Connectivity
I²C, SPI, UART/USART
Peripherals
Brown-out Detect/Reset, POR, PWM, WDT
Number Of I /o
32
Program Memory Size
32KB (16K x 16)
Program Memory Type
FLASH
Eeprom Size
1K x 8
Ram Size
2K x 8
Voltage - Supply (vcc/vdd)
2.7 V ~ 5.5 V
Data Converters
A/D 8x10b
Oscillator Type
Internal
Operating Temperature
-40°C ~ 125°C
Package / Case
44-TQFP, 44-VQFP
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
- Current page: 40 of 377
- Download datasheet (7Mb)
7.12.2
40
ATmega164P/324P/644P
CLKPR – Clock Prescale Register
• Bit 7 – CLKPCE: Clock Prescaler Change Enable
The CLKPCE bit must be written to logic one to enable change of the CLKPS bits. The CLKPCE
bit is only updated when the other bits in CLKPR are simultaneously written to zero. CLKPCE is
cleared by hardware four cycles after it is written or when CLKPS bits are written. Rewriting the
CLKPCE bit within this time-out period does neither extend the time-out period, nor clear the
CLKPCE bit.
• Bits 3:0 – CLKPS3:0: Clock Prescaler Select Bits 3 - 0
These bits define the division factor between the selected clock source and the internal system
clock. These bits can be written run-time to vary the clock frequency to suit the application
requirements. As the divider divides the master clock input to the MCU, the speed of all synchro-
nous peripherals is reduced when a division factor is used. The division factors are given in
Table 7-16 on page
The CKDIV8 Fuse determines the initial value of the CLKPS bits. If CKDIV8 is unprogrammed,
the CLKPS bits will be reset to “0000”. If CKDIV8 is programmed, CLKPS bits are reset to
“0011”, giving a division factor of 8 at start up. This feature should be used if the selected clock
source has a higher frequency than the maximum frequency of the device at the present operat-
ing conditions. Note that any value can be written to the CLKPS bits regardless of the CKDIV8
Fuse setting. The Application software must ensure that a sufficient division factor is chosen if
the selected clock source has a higher frequency than the maximum frequency of the device at
the present operating conditions. The device is shipped with the CKDIV8 Fuse programmed.
Table 7-16.
Bit
(0x61)
Read/Write
Initial Value
CLKPS3
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
Clock Prescaler Select
CLKPCE
R/W
7
0
CLKPS2
40.
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
R
6
0
–
CLKPS1
R
5
0
–
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
R
4
0
–
CLKPS0
CLKPS3
R/W
3
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
CLKPS2
See Bit Description
R/W
2
Clock Division Factor
CLKPS1
R/W
1
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
128
256
16
32
64
CLKPS0
1
2
4
8
R/W
0
7674F–AVR–09/09
CLKPR
Related parts for ATMEGA324P-15AZ
Image
Part Number
Description
Manufacturer
Datasheet
Request
R
Part Number:
Description:
Manufacturer:
ATMEL Corporation
Datasheet:
Part Number:
Description:
Manufacturer:
Atmel Corporation
Datasheet:
Part Number:
Description:
Manufacturer:
ATMEL Corporation
Datasheet:
Part Number:
Description:
IC AVR MCU 32K 16MHZ 5V 44-QFN
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
IC AVR MCU 32K 16MHZ 5V 40DIP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
IC AVR MCU 32K 16MHZ 5V 44TQFP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
IC AVR MCU 32K 16MHZ IND 40-DIP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
IC AVR MCU 32K 16MHZ IND 44-TQFP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
MCU AVR 32KB FLASH 16MHZ 44TQFP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
MCU AVR 32KB FLASH 16MHZ 44QFN
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
MCU AVR 32K FLASH 16MHZ 44-TQFP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
IC AVR MCU 32K 16MHZ COM 40-DIP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
IC AVR MCU 32K 16MHZ COM 44-QFN
Manufacturer:
Atmel
Datasheet: