ATMEGA48-20MJ Atmel, ATMEGA48-20MJ Datasheet - Page 133
![no-image](/images/manufacturer_photos/0/0/78/atmel_sml.jpg)
ATMEGA48-20MJ
Manufacturer Part Number
ATMEGA48-20MJ
Description
IC AVR MCU 4K 5V 20MHZ 32-QFN
Manufacturer
Atmel
Series
AVR® ATmegar
Specifications of ATMEGA48-20MJ
Core Processor
AVR
Core Size
8-Bit
Speed
20MHz
Connectivity
I²C, SPI, UART/USART
Peripherals
Brown-out Detect/Reset, POR, PWM, WDT
Number Of I /o
23
Program Memory Size
4KB (2K x 16)
Program Memory Type
FLASH
Eeprom Size
256 x 8
Ram Size
512 x 8
Voltage - Supply (vcc/vdd)
2.7 V ~ 5.5 V
Data Converters
A/D 8x10b
Oscillator Type
Internal
Operating Temperature
-40°C ~ 85°C
Package / Case
32-VQFN Exposed Pad, 32-HVQFN, 32-SQFN, 32-DHVQFN
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Other names
ATMEGA48-24MJ
ATMEGA48-24MJ
ATMEGA48-24MJ
- Current page: 133 of 378
- Download datasheet (8Mb)
15.11.4
15.11.5
15.11.6
2545S–AVR–07/10
TCNT1H and TCNT1L – Timer/Counter1
OCR1AH and OCR1AL – Output Compare Register 1 A
OCR1BH and OCR1BL – Output Compare Register 1 B
The FOC1A/FOC1B bits are always read as zero.
The two Timer/Counter I/O locations (TCNT1H and TCNT1L, combined TCNT1) give direct
access, both for read and for write operations, to the Timer/Counter unit 16-bit counter. To
ensure that both the high and low bytes are read and written simultaneously when the CPU
accesses these registers, the access is performed using an 8-bit temporary High Byte Register
(TEMP). This temporary register is shared by all the other 16-bit registers.
Registers” on page 109.
Modifying the counter (TCNT1) while the counter is running introduces a risk of missing a com-
pare match between TCNT1 and one of the OCR1x Registers.
Writing to the TCNT1 Register blocks (removes) the compare match on the following timer clock
for all compare units.
The Output Compare Registers contain a 16-bit value that is continuously compared with the
counter value (TCNT1). A match can be used to generate an Output Compare interrupt, or to
generate a waveform output on the OC1x pin.
The Output Compare Registers are 16-bit in size. To ensure that both the high and low bytes are
written simultaneously when the CPU writes to these registers, the access is performed using an
8-bit temporary High Byte Register (TEMP). This temporary register is shared by all the other
16-bit registers.
Bit
(0x85)
(0x84)
Read/Write
Initial Value
Bit
(0x89)
(0x88)
Read/Write
Initial Value
Bit
(0x8B)
(0x8A)
Read/Write
Initial Value
See “Accessing 16-bit Registers” on page 109.
R/W
R/W
R/W
7
0
7
0
7
0
R/W
R/W
R/W
6
0
6
0
6
0
R/W
R/W
R/W
5
0
5
0
5
0
R/W
R/W
R/W
4
0
4
0
4
0
OCR1A[15:8]
OCR1B[15:8]
TCNT1[15:8]
OCR1A[7:0]
OCR1B[7:0]
TCNT1[7:0]
R/W
R/W
R/W
3
0
3
0
3
0
R/W
R/W
R/W
ATmega48/88/168
2
0
2
0
2
0
R/W
R/W
R/W
1
0
1
0
1
0
See “Accessing 16-bit
R/W
R/W
R/W
0
0
0
0
0
0
OCR1AH
OCR1BH
OCR1AL
OCR1BL
TCNT1H
TCNT1L
133
Related parts for ATMEGA48-20MJ
Image
Part Number
Description
Manufacturer
Datasheet
Request
R
![ATMEGA48-20AI](/photos/6/91/69154/313-32-tqfp_tmb.jpg)
Part Number:
Description:
IC AVR MCU 4K 5V 20MHZ 32-TQFP
Manufacturer:
Atmel
Datasheet:
![ATmega48](/images/manufacturer_photos/0/0/79/atmel_corporation_tmb.jpg)
Part Number:
Description:
Manufacturer:
Atmel Corporation
Datasheet:
![ATmega48 Automotive](/images/manufacturer_photos/0/0/79/atmel_corporation_tmb.jpg)
Part Number:
Description:
Manufacturer:
Atmel Corporation
Datasheet:
![ATMEGA48-20AU](/photos/6/91/69154/313-32-tqfp_tmb.jpg)
Part Number:
Description:
IC AVR MCU 4K 20MHZ 5V 32TQFP
Manufacturer:
Atmel
Datasheet:
![ATMEGA48-20PU](/photos/7/21/72189/453-28-dip_tmb.jpg)
Part Number:
Description:
IC AVR MCU 4K 20MHZ 5V 28DIP
Manufacturer:
Atmel
Datasheet:
![ATMEGA48-20MU](/photos/12/32/123213/atmega48-20mu_tmb.jpg)
Part Number:
Description:
IC AVR MCU 4K 20MHZ 5V 32-QFN
Manufacturer:
Atmel
Datasheet:
![ATMEGA48-20AJ](/photos/6/91/69154/313-32-tqfp_tmb.jpg)
Part Number:
Description:
IC AVR MCU 4K 5V 20MHZ 32-TQFP
Manufacturer:
Atmel
Datasheet:
![ATMEGA48-20MI](/images/manufacturer_photos/0/0/78/atmel_tmb.jpg)
Part Number:
Description:
IC AVR MCU 4K 5V 20MHZ 32-QFN
Manufacturer:
Atmel
Datasheet:
![ATMEGA48-20PI](/photos/7/21/72189/453-28-dip_tmb.jpg)
Part Number:
Description:
IC AVR MCU 4K 5V 20MHZ 28-DIP
Manufacturer:
Atmel
Datasheet:
![ATMEGA48-20PJ](/photos/7/21/72189/453-28-dip_tmb.jpg)
Part Number:
Description:
IC AVR MCU 4K 5V 20MHZ 28-DIP
Manufacturer:
Atmel
Datasheet:
![ATMEGA48-20MMU](/photos/12/13/121311/atmega48-20mmu_tmb.jpg)
Part Number:
Description:
IC AVR MCU 4K FLASH 20MHZ 28QFN
Manufacturer:
Atmel
Datasheet:
![ATMEGA48-20MUR](/images/manufacturer_photos/0/0/78/atmel_tmb.jpg)
Part Number:
Description:
MCU AVR 4KB FLASH 20MHZ 32QFN
Manufacturer:
Atmel
Datasheet: