ATMEGA325P-20MU Atmel, ATMEGA325P-20MU Datasheet - Page 221

• Manufacturer Part Number: ATMEGA325P-20MU
• Description: IC MCU AVR 32K FLASH 64-QFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA325P-20MU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: SPI, UART/USART, USI
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 54
• 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 ~ 85°C
• Package / Case: 64-MLF®, 64-QFN
• Processor Series: ATMEGA32x
• Core: AVR8
• Data Bus Width: 8 bit
• Data Ram Size: 2 KB
• Interface Type: SPI, UART, USI
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 54
• Number Of Timers: 3
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Development Tools By Supplier: ATAVRDRAGON, ATSTK500, ATSTK600, ATAVRISP2, ATAVRONEKIT
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 8 Channel
• For Use With: ATSTK600-TQFP64 - STK600 SOCKET/ADAPTER 64-TQFP770-1007 - ISP 4PORT ATMEL AVR MCU SPI/JTAGATAVRISP2 - PROGRAMMER AVR IN SYSTEM
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: ATMEGA325P-16MU; ATMEGA325P-16MU

21.9.3
21.9.3.1
21.9.3.2
8023F–AVR–07/09
ADCL and ADCH – The ADC Data Register
ADLAR = 0
ADLAR = 1
Table 21-4.
When an ADC conversion is complete, the result is found in these two registers. When ADCL is
read, the ADC Data Register is not updated until ADCH is read. Consequently, if the result is left
adjusted and no more than 8-bit precision is required, it is sufficient to read ADCH. Otherwise,
ADCL must be read first, then ADCH.
The ADLAR bit in ADMUX, and the MUXn bits in ADMUX affect the way the result is read from
the registers. If ADLAR is set, the result is left adjusted. If ADLAR is cleared (default), the result
is right adjusted.
• ADC9:0: ADC Conversion Result
These bits represent the result from the conversion, as detailed in
page
Bit
(0x79)
(0x78)
Read/Write
Initial Value
Bit
(0x79)
(0x78)
Read/Write
Initial Value
216.
ADPS2
1
1
1
1
ADC Prescaler Selections (Continued)
ADC7
ADC9
ADC1
15
15
R
R
–
7
0
0
R
R
7
0
0
ADC6
ADC8
ADC0
14
14
ADPS1
R
R
R
R
–
6
0
0
6
0
0
0
0
1
1
ADC5
ADC7
13
13
R
R
R
R
–
5
0
0
–
5
0
0
ADC4
ADC6
12
12
R
R
R
R
–
4
0
0
0
–
4
0
ADPS0
0
1
0
1
ADC3
ADC5
11
11
R
R
–
3
0
0
R
R
–
3
0
0
ATmega325P/3250P
ADC2
ADC4
10
10
R
R
–
2
0
0
R
R
–
2
0
0
”ADC Conversion Result” on
ADC9
ADC1
ADC3
Division Factor
R
R
9
1
0
0
R
R
9
–
1
0
0
128
16
32
64
ADC8
ADC0
ADC2
8
0
R
R
0
0
R
R
8
–
0
0
0
ADCH
ADCL
ADCH
ADCL
221