ATmega32 Atmel Corporation, ATmega32 Datasheet - Page 139

• Manufacturer Part Number: ATmega32
• Manufacturer: Atmel Corporation

Specifications of ATmega32

• Flash (kbytes): 32 Kbytes
• Pin Count: 44
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 32
• Ext Interrupts: 3
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Twi (i2c): 1
• Uart: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 2
• Eeprom (bytes): 1024
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 2.7 to 5.5
• Operating Voltage (vcc): 2.7 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 3
• Output Compare Channels: 4
• Input Capture Channels: 1
• Pwm Channels: 4
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

Data Modes
2503Q–AVR–02/11
There are four combinations of SCK phase and polarity with respect to serial data, which are
determined by control bits CPHA and CPOL. The SPI data transfer formats are shown in
67
ensuring sufficient time for data signals to stabilize. This is clearly seen by summarizing
56
Table 59. CPOL and CPHA Functionality
Figure 67. SPI Transfer Format with CPHA = 0
Figure 68. SPI Transfer Format with CPHA = 1
and
and
CPOL = 0, CPHA = 0
CPOL = 0, CPHA = 1
CPOL = 1, CPHA = 0
CPOL = 1, CPHA = 1
Table
Figure
SCK (CPOL = 0)
mode 0
SCK (CPOL = 1)
mode 2
SAMPLE I
MOSI/MISO
CHANGE 0
MOSI PIN
CHANGE 0
MISO PIN
SCK (CPOL = 0)
mode 1
SCK (CPOL = 1)
mode 3
SAMPLE I
MOSI/MISO
CHANGE 0
MOSI PIN
CHANGE 0
MISO PIN
SS
SS
MSB first (DORD = 0)
LSB first (DORD = 1)
MSB first (DORD = 0)
LSB first (DORD = 1)
57, as done below:
68. Data bits are shifted out and latched in on opposite edges of the SCK signal,
MSB
LSB
Sample (Falling)
Sample (Rising)
Leading Edge
Setup (Rising)
Setup (Falling)
MSB
LSB
Bit 6
Bit 1
Bit 6
Bit 1
Bit 5
Bit 2
Bit 5
Bit 2
Bit 4
Bit 3
Bit 4
Bit 3
Sample (Falling)
Sample (Rising)
Setup (Falling)
Trailing Edge
Setup (Rising)
Bit 3
Bit 4
Bit 3
Bit 4
Bit 2
Bit 5
Bit 2
Bit 5
ATmega32(L)
Bit 1
Bit 6
Bit 1
Bit 6
SPI Mode
LSB
MSB
0
1
2
3
LSB
MSB
Figure
Table
139