ATMEGA16-16AU SL383 Atmel, ATMEGA16-16AU SL383 Datasheet - Page 72

• Manufacturer Part Number: ATMEGA16-16AU SL383
• Description: IC MCU 8BIT 16KB FLASH 44TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA16-16AU SL383

• 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: 16KB (8K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 512 x 8
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-TQFP, 44-VQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Definitions
Timer/Counter
Clock Sources
Counter Unit
2466T–AVR–07/10
Unit” on page 73.
which can be used to generate an output compare interrupt request.
Many register and bit references in this document are written in general form. A lower case “n”
replaces the Timer/Counter number, in this case 0. However, when using the register or bit
defines in a program, the precise form must be used, that is, TCNT0 for accessing
Timer/Counter0 counter value and so on.
The definitions in
Table 37. Definitions
The Timer/Counter can be clocked by an internal or an external clock source. The clock source
is selected by the clock select logic which is controlled by the clock select (CS02:0) bits located
in the Timer/Counter Control Register (TCCR0). For details on clock sources and prescaler, see
“Timer/Counter0 and Timer/Counter1 Prescalers” on page
The main part of the 8-bit Timer/Counter is the programmable bi-directional counter unit.
28
Figure 28. Counter Unit Block Diagram
Signal description (internal signals):
Depending of the mode of operation used, the counter is cleared, incremented, or decremented
at each timer clock (clk
selected by the Clock Select bits (CS02:0). When no clock source is selected (CS02:0 = 0) the
timer is stopped. However, the TCNT0 value can be accessed by the CPU, regardless of
BOTTOM
MAX
TOP
count
direction
clear
clk
TOP
BOTTOM
shows a block diagram of the counter and its surroundings.
Tn
DATA BUS
The counter reaches the BOTTOM when it becomes 0x00.
The counter reaches its MAXimum when it becomes 0xFF (decimal 255).
The counter reaches the TOP when it becomes equal to the highest
value in the count sequence. The TOP value can be assigned to be the
fixed value 0xFF (MAX) or the value stored in the OCR0 Register. The
assignment is dependent on the mode of operation.
Increment or decrement TCNT0 by 1.
Select between increment and decrement.
Clear TCNT0 (set all bits to zero).
Timer/Counter clock, referred to as clk
Signalize that TCNT0 has reached maximum value.
Signalize that TCNT0 has reached minimum value (zero).
TCNTn
Table 37
for details. The compare match event will also set the Compare Flag (OCF0)
T0
). clk
are also used extensively throughout the document.
T0
direction
can be generated from an external or internal clock source,
count
clear
BOTTOM
Control Logic
TOP
TOVn
(Int. Req.)
clk
T0
Tn
in the following.
87.
Clock Select
( From Prescaler )
Detector
Edge
ATmega16(L)
Tn
Figure
72