ATmega48 Automotive Atmel Corporation, ATmega48 Automotive Datasheet - Page 252

• Manufacturer Part Number: ATmega48 Automotive
• Manufacturer: Atmel Corporation

Specifications of ATmega48 Automotive

• Flash (kbytes): 4 Kbytes
• Pin Count: 32
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 12
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 23
• Ext Interrupts: 24
• Usb Speed: No
• Usb Interface: No
• Spi: 2
• Twi (i2c): 1
• Uart: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 0.5
• Eeprom (bytes): 256
• Self Program Memory: NO
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 125
• I/o Supply Class: 2.7 to 5.5
• Operating Voltage (vcc): 2.7 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 3
• Output Compare Channels: 6
• Input Capture Channels: 1
• Pwm Channels: 6
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

21.6.3.2
21.6.4
252
ATmega48/88/168 Automotive
ADC Control and Status Register B – ADCSRB
ADLAR = 1
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 7, 5:3 – Res: Reserved Bits
These bits are reserved for future use. To ensure compatibility with future devices, these bist
must be written to zero when ADCSRB is written.
• Bit 2:0 – ADTS2:0: ADC Auto Trigger Source
If ADATE in ADCSRA is written to one, the value of these bits selects which source will trigger
an ADC conversion. If ADATE is cleared, the ADTS2:0 settings will have no effect. A conversion
will be triggered by the rising edge of the selected Interrupt Flag. Note that switching from a trig-
ger source that is cleared to a trigger source that is set, will generate a positive edge on the
trigger signal. If ADEN in ADCSRA is set, this will start a conversion. Switching to Free Running
mode (ADTS[2:0]=0) will not cause a trigger event, even if the ADC Interrupt Flag is set
Bit
Read/Write
Initial Value
Bit
Read/Write
Initial Value
249.
ADC9
ADC1
15
R
R
7
0
0
R
7
–
0
ADC8
ADC0
ACME
R/W
14
R
R
6
0
0
6
0
ADC7
13
R
R
–
5
0
0
R
5
–
0
ADC6
12
R
R
–
4
0
0
R
4
–
0
ADC5
11
R
R
–
3
0
0
R
3
–
0
ADTS2
ADC4
R/W
10
R
R
–
2
0
0
2
0
“ADC Conversion Result” on
ADTS1
ADC3
R/W
R
R
9
–
1
0
0
1
0
ADTS0
ADC2
R/W
R
R
8
–
0
0
0
0
0
7530I–AVR–02/10
ADCSRB
.
ADCH
ADCL