Datasheet

22.11.4. ADC Data Register Low and High Byte (ADLAR=0)
The ADCL and ADCH register pair represents the 16-bit value, ADC Data Register. The low byte [7:0]
(suffix L) is accessible at the original offset. The high byte [15:8] (suffix H) can be accessed at offset +
0x01. For more details on reading and writing 16-bit registers, refer to Accessing 16-bit Registers.
When an ADC conversion is complete, the result is found in these two registers.
If differential channels are used, the result is presented in two’s complement form.
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 and the MUXn bits in ADMUX affect the way the result is read from the registers. If
ADLAR is set (ADLAR=1), the result is left adjusted. If ADLAR is cleared (ADLAR=0 which is the default
value), the result is right adjusted.
Name: ADCL and ADCH
Offset: 0x78
Reset: 0x00
Property: ADLAR = 0
Bit 15 14 13 12 11 10 9 8
ADC9 ADC8
Access
R R
Reset 0 0
Bit 7 6 5 4 3 2 1 0
ADC7 ADC6 ADC5 ADC4 ADC3 ADC2 ADC1 ADC0
Access
R R R R R R R R
Reset 0 0 0 0 0 0 0 0
Bits 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 – ADCn: ADC Conversion Result
These bits represent the result from the conversion. Refer to ADC Conversion Result for details.
Atmel ATmega16M1/32M1/64M1 [DATASHEET]
Atmel-8209F-ATmega16M1/32M1/64M1_Datasheet_Complete-10/2016
326