ATTINY48-PU Atmel, ATTINY48-PU Datasheet - Page 97

• Manufacturer Part Number: ATTINY48-PU
• Description: MCU AVR 4K ISP FLASH 1.8V 28-DIP
• Manufacturer: Atmel
• Series: AVR® ATtinyr

Specifications of ATTINY48-PU

• 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 6x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 28-DIP (0.300", 7.62mm)
• Processor Series: ATTINY4x
• Core: AVR8
• Data Bus Width: 8 bit
• Data Ram Size: 256 B
• Interface Type: 2-Wire/I2S/SPI
• Maximum Clock Frequency: 12 MHz
• Number Of Programmable I/os: 28
• Number Of Timers: 2
• Maximum Operating Temperature: + 85 C
• Mounting Style: Through Hole
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Development Tools By Supplier: ATAVRDRAGON, ATSTK500, ATSTK600, ATAVRISP2, ATAVRONEKIT
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 6-ch x 10-bit
• Package: 28PDIP
• Device Core: AVR
• Family Name: ATtiny
• Maximum Speed: 12 MHz
• Operating Supply Voltage: 2.5|3.3|5 V
• For Use With: ATSTK600 - DEV KIT FOR AVR/AVR32ATAVRDRAGON - KIT DRAGON 32KB FLASH MEM AVRATAVRISP2 - PROGRAMMER AVR IN SYSTEM
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

12.7
8008G–AVR–04/11
Output Compare Units
Using the Input Capture unit in any mode of operation when the TOP value (resolution) is
actively changed during operation, is not recommended.
Measurement of an external signal’s duty cycle requires that the trigger edge is changed after
each capture. Changing the edge sensing must be done as early as possible after the ICR1
Register has been read. After a change of the edge, the Input Capture Flag (ICF1) must be
cleared by software (writing a logical one to the I/O bit location). For measuring frequency only,
the clearing of the ICF1 Flag is not required (if an interrupt handler is used).
The 16-bit comparator continuously compares TCNT1 with the Output Compare Register
(OCR1x). If TCNT equals OCR1x the comparator signals a match. A match will set the Output
Compare Flag (OCF1x) at the next timer clock cycle. If enabled (OCIE1x = 1), the Output Com-
pare Flag generates an Output Compare interrupt. The OCF1x Flag is automatically cleared
when the interrupt is executed. Alternatively the OCF1x Flag can be cleared by software by writ-
ing a logical one to its I/O bit location. The Waveform Generator uses the match signal to
generate an output according to operating mode set by the Waveform Generation mode
(WGM1[3:0]) bits and Compare Output mode (COM1x[1:0]) bits. The TOP and BOTTOM signals
are used by the Waveform Generator for handling the special cases of the extreme values in
some modes of operation
A special feature of Output Compare unit A allows it to define the Timer/Counter TOP value (i.e.,
counter resolution). In addition to the counter resolution, the TOP value defines the period time
for waveforms generated by the Waveform Generator.
Figure 12-4
bit names indicates the device number (n = 1 for Timer/Counter 1), and the “x” indicates Output
Compare unit (A/B). The elements of the block diagram that are not directly a part of the Output
Compare unit are gray shaded.
Figure 12-4. Output Compare Unit, Block Diagram
shows a block diagram of the Output Compare unit. The small “n” in the register and
OCRnxH Buf. (8-bit)
(See “Modes of Operation” on page
OCRnxH (8-bit)
BOTTOM
OCRnx
TEMP (8-bit)
TOP
OCRnx (16-bit Register)
Buffer (16-bit Register)
OCRnxL Buf. (8-bit)
OCRnxL (8-bit)
DATA BUS
Waveform Generator
WGMn[3:0]
=
(16-bit Comparator )
(8-bit)
COMnx[1:0]
TCNTnH (8-bit)
OCFnx (Int.Req.)
100.)
TCNTn (16-bit Counter)
ATtiny48/88
TCNTnL (8-bit)
OCnx
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