ATmega32

Image: 
ATmega32 | Mega32 AVR Microcontroller Image
DataSheet: 

ATmega32 is very much similar to ATmega16 microcontroller with certain differences which are discussed below. ATmega32 is an 8-bit high performance microcontroller of Atmel’s Mega AVR family. Atmega32 is based on enhanced RISC (Reduced Instruction Set Computing) architecture with 131 powerful instructions. Most of the instructions execute in one machine cycle. Atmega32 can work on a maximum frequency of 16MHz.

The differences between ATmega32 and ATmega16 can be summarized as follows:
1.   ATmega32 has 32 KB programmable flash memory, static RAM of 2 KB and EEPROM of 1 KB. The endurance cycle of flash memory and EEPROM is 10,000 and 100,000, respectively.
 
 
ATmega32
ATmega16
RAM
2 KB
1 KB
Flash
32 KB
16 KB
EEPROM
1 KB
512 bytes
 
2.    The Bootloader area, the NRWW section starts at word 0x3800 in ATmega32 while in ATmega16 it starts at 0x1C00.
3.    ATmega32 has a different interrupt table, the table given below shows the difference. More details can be obtained from the respective datasheets.
 
Vector #
ATmega32
ATmega16
1
Reset
Reset
2
INT0
INT0
3
INT1
INT1
4
INT2
Timer2 COMP
5
Timer2 COMP
Timer2 OVF
6
Timer2 OVF
Timer1 CAPT
7
Timer1 CAPT
Timer1 COMPA
8
Timer1 COMPA
Timer1 COMPB
9
Timer1 COMPB
Timer1 OVF
10
Timer1 OVF
Timer0 OVF
11
Timer0 COMP
SPI, STC
12
Timer0 OVF
USART, RXC
13
SPI, STC
USART, UDRE
14
USART, RXC
USART, TXC
15
USART, UDRE
ADC
16
USART, TXC
EE_RDY
17
ADC
ANA_COMP
18
EE_RDY
TWI
19
ANA_COMP
INT2
20
TWI
Timer0 COMP
21
SPM_RDY
SPM_RDY
 
4.      In MCUCR register, the SM2 and SE bits are swapped, i.e., the SM2 bit is bit7 and SE bit is bit6 in MCUCR register in ATmega32. 
 
Pin Diagram: 
ATmega32 | Mega32 AVR Microcontroller pin diagram, pinout
Pin Description: 


Pin No.
Pin name
Description
Alternate Function
1
(XCK/T0) PB0
I/O PORTB, Pin 0
T0: Timer0 External Counter Input.
XCK : USART External Clock I/O
2
(T1) PB1
I/O PORTB, Pin 1
T1:Timer1 External Counter Input
3
(INT2/AIN0) PB2
I/O PORTB, Pin 2
AIN0: Analog Comparator Positive I/P
INT2: External Interrupt 2 Input
4
(OC0/AIN1) PB3
I/O PORTB, Pin 3
AIN1: Analog Comparator Negative I/P
OC0 : Timer0 Output Compare Match Output
5
(SS) PB4
I/O PORTB, Pin 4
In System Programmer (ISP)
Serial Peripheral Interface (SPI)
6
(MOSI) PB5
I/O PORTB, Pin 5
7
(MISO) PB6
I/O PORTB, Pin 6
8
(SCK) PB7
I/O PORTB, Pin 7
9
RESET
Reset Pin, Active Low Reset
 
10
Vcc
Vcc = +5V
 
11
GND
GROUND
12
XTAL2
Output to Inverting Oscillator Amplifier
13
XTAL1
Input to Inverting Oscillator Amplifier
14
(RXD) PD0
I/O PORTD, Pin 0
USART Serial Communication Interface
15
(TXD) PD1
I/O PORTD, Pin 1
16
(INT0) PD2
I/O PORTD, Pin 2
External Interrupt INT0
17
(INT1) PD3
I/O PORTD, Pin 3
External Interrupt INT1
18
(OC1B) PD4
I/O PORTD, Pin 4
PWM Channel Outputs
19
(OC1A) PD5
I/O PORTD, Pin 5
20
(ICP) PD6
I/O PORTD, Pin 6
Timer/Counter1 Input Capture Pin
21
PD7 (OC2)
I/O PORTD, Pin 7
Timer/Counter2 Output Compare Match Output
22
PC0 (SCL)
I/O PORTC, Pin 0
TWI Interface
23
PC1 (SDA)
I/O PORTC, Pin 1
24
PC2 (TCK)
I/O PORTC, Pin 2
JTAG Interface
25
PC3 (TMS)
I/O PORTC, Pin 3
26
PC4 (TDO)
I/O PORTC, Pin 4
27
PC5 (TDI)
I/O PORTC, Pin 5
28
PC6 (TOSC1)
I/O PORTC, Pin 6
Timer Oscillator Pin 1
29
PC7 (TOSC2)
I/O PORTC, Pin 7
Timer Oscillator Pin 2
30
AVcc
Voltage Supply = Vcc for ADC
31
GND
GROUND
32
AREF
Analog Reference Pin for ADC
33
PA7 (ADC7)
I/O PORTA, Pin 7
ADC Channel 7
34
PA6 (ADC6)
I/O PORTA, Pin 6
ADC Channel 6
35
PA5 (ADC5)
I/O PORTA, Pin 5
ADC Channel 5
36
PA4 (ADC4)
I/O PORTA, Pin 4
ADC Channel 4
37
PA3 (ADC3)
I/O PORTA, Pin 3
ADC Channel 3
38
PA2 (ADC2)
I/O PORTA, Pin 2
ADC Channel 2
39
PA1 (ADC1)
I/O PORTA, Pin 1
ADC Channel 1
40
PA0 (ADC0)
I/O PORTA, Pin 0
ADC Channel 0