ATmega168P Atmel Corporation, ATmega168P Datasheet - Page 96

no-image

ATmega168P

Manufacturer Part Number
ATmega168P
Description
Manufacturer
Atmel Corporation
Datasheets

Specifications of ATmega168P

Flash (kbytes)
16 Kbytes
Pin Count
32
Max. Operating Frequency
20 MHz
Cpu
8-bit AVR
# Of Touch Channels
16
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
Yes
Crypto Engine
No
Sram (kbytes)
1
Eeprom (bytes)
512
Self Program Memory
YES
Dram Memory
No
Nand Interface
No
Picopower
Yes
Temp. Range (deg C)
-40 to 85
I/o Supply Class
1.8 to 5.5
Operating Voltage (vcc)
1.8 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

Available stocks

Company
Part Number
Manufacturer
Quantity
Price
Part Number:
ATmega168P-20AN
Manufacturer:
Atmel
Quantity:
10 000
Part Number:
ATmega168P-20ANR
Manufacturer:
Atmel
Quantity:
10 000
Part Number:
ATmega168P-20AU
Manufacturer:
ATMEL
Quantity:
1 250
Part Number:
ATmega168P-20AU
Manufacturer:
Atmel
Quantity:
10 000
Part Number:
ATmega168P-20AU
Manufacturer:
ATMEL
Quantity:
1 011
Part Number:
ATmega168P-20AUR
Manufacturer:
Atmel
Quantity:
10 000
Part Number:
ATmega168P-20MU
Manufacturer:
ATMEL
Quantity:
12 000
Part Number:
ATmega168PA
Manufacturer:
ATMEL
Quantity:
2 650
Part Number:
ATmega168PA-15AZ
Manufacturer:
VAC
Quantity:
120
Part Number:
ATmega168PA-15AZ
Manufacturer:
Atmel
Quantity:
10 000
Part Number:
ATmega168PA-15MZ
Manufacturer:
TOSHIBA
Quantity:
1 000
Part Number:
ATmega168PA-AU
Manufacturer:
Atmel
Quantity:
2 902
Company:
Part Number:
ATmega168PA-AU
Manufacturer:
MICROCHIP
Quantity:
5 502
Company:
Part Number:
ATmega168PA-AU
Manufacturer:
ATMEL
Quantity:
2 300
Part Number:
ATmega168PA-AU
Manufacturer:
ATMEL
Quantity:
200
Company:
Part Number:
ATmega168PA-AUR
Manufacturer:
ATMEL
Quantity:
32
15.5.1
15.5.2
15.5.3
15.6
96
Compare Match Output Unit
ATmega48P/88P/168P
Force Output Compare
Compare Match Blocking by TCNT0 Write
Using the Output Compare Unit
The OCR0x Register access may seem complex, but this is not case. When the double buffering
is enabled, the CPU has access to the OCR0x Buffer Register, and if double buffering is dis-
abled the CPU will access the OCR0x directly.
In non-PWM waveform generation modes, the match output of the comparator can be forced by
writing a one to the Force Output Compare (FOC0x) bit. Forcing compare match will not set the
OCF0x Flag or reload/clear the timer, but the OC0x pin will be updated as if a real compare
match had occurred (the COM0x1:0 bits settings define whether the OC0x pin is set, cleared or
toggled).
All CPU write operations to the TCNT0 Register will block any compare match that occur in the
next timer clock cycle, even when the timer is stopped. This feature allows OCR0x to be initial-
ized to the same value as TCNT0 without triggering an interrupt when the Timer/Counter clock is
enabled.
Since writing TCNT0 in any mode of operation will block all compare matches for one timer clock
cycle, there are risks involved when changing TCNT0 when using the Output Compare Unit,
independently of whether the Timer/Counter is running or not. If the value written to TCNT0
equals the OCR0x value, the compare match will be missed, resulting in incorrect waveform
generation. Similarly, do not write the TCNT0 value equal to BOTTOM when the counter is
downcounting.
The setup of the OC0x should be performed before setting the Data Direction Register for the
port pin to output. The easiest way of setting the OC0x value is to use the Force Output Com-
pare (FOC0x) strobe bits in Normal mode. The OC0x Registers keep their values even when
changing between Waveform Generation modes.
Be aware that the COM0x1:0 bits are not double buffered together with the compare value.
Changing the COM0x1:0 bits will take effect immediately.
The Compare Output mode (COM0x1:0) bits have two functions. The Waveform Generator uses
the COM0x1:0 bits for defining the Output Compare (OC0x) state at the next compare match.
Also, the COM0x1:0 bits control the OC0x pin output source.
schematic of the logic affected by the COM0x1:0 bit setting. The I/O Registers, I/O bits, and I/O
pins in the figure are shown in bold. Only the parts of the general I/O port control registers (DDR
and PORT) that are affected by the COM0x1:0 bits are shown. When referring to the OC0x
state, the reference is for the internal OC0x Register, not the OC0x pin. If a system reset occur,
the OC0x Register is reset to “0”.
Figure 15-4
shows a simplified
8025M–AVR–6/11

Related parts for ATmega168P