ATTINY48-MMHR Atmel, ATTINY48-MMHR Datasheet - Page 81

• Manufacturer Part Number: ATTINY48-MMHR
• Description: MCU AVR 4KB FLASH 12MHZ 28QFN
• Manufacturer: Atmel
• Series: AVR® ATtinyr

Specifications of ATTINY48-MMHR

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 12MHz
• Connectivity: I²C, SPI
• Peripherals: Brown-out Detect/Reset, POR, WDT
• Number Of I /o: 24
• Program Memory Size: 4KB (2K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 64 x 8
• Ram Size: 256 x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: *
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

11.2.2
11.3
11.4
8008G–AVR–04/11
Timer/Counter Clock Sources
Counter Unit
Registers
ter or bit defines in a program, the precise form must be used, i.e., TCNT0 for accessing
Timer/Counter0 counter value and so on.
The definitions in
Table 11-1.
The Timer/Counter (TCNT0) and Output Compare Registers (OCR0A and OCR0B) are 8-bit
registers. Interrupt request (abbreviated to Int.Req. in the figure) signals are all visible in the
Timer Interrupt Flag Register (TIFR0). All interrupts are individually masked with the Timer Inter-
rupt Mask Register (TIMSK0). TIFR0 and TIMSK0 are not shown in the figure.
The Timer/Counter can be clocked internally, via the prescaler, or by an external clock source on
the T0 pin. The Clock Select logic block controls which clock source and edge the Timer/Counter
uses to increment its value. The Timer/Counter is inactive when no clock source is selected. The
output from the Clock Select logic is referred to as the timer clock (clk
The Output Compare Registers (OCR0A and OCR0B) are compared with the Timer/Counter
value at all times. The compare match event will also set the Compare Flag (OCF0A or OCF0B)
which can be used to generate an Output Compare interrupt request.
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 (CS0[2:0]) bits
located in the Timer/Counter Control Register (TCCR0A). For details on clock sources and pres-
caler, see
The main part of the 8-bit Timer/Counter is the programmable bi-directional counter unit.
11-2
Figure 11-2. Counter Unit Block Diagram
MAX
TOP
shows a block diagram of the counter and its surroundings.
DATA BUS
“Timer/Counter0 and Timer/Counter1 Prescalers” on page
TCNTn
Definitions
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 OCR0A Register. The assignment is depen-
dent on the mode of operation.
Table 11-1
are used extensively throughout the document.
count
clear
Control Logic
top
TOVn
(Int.Req.)
clk
Tn
Clock Select
117.
( From Prescaler )
T0
Detector
Edge
).
ATtiny48/88
Figure
Tn
81