Atmel ATmega32M1 User Manual

160
7647H–AVR–03/12
Atmel ATmega16/32/64/M1/C1
When the SPI is enabled, the data direction of the MOSI, MISO, SCK, and SS pins is overridden
according to Table 15-1. For more details on automatic port overrides, refer to “Alternate Port
Functions” on page 67.
Note: 1. See “Alternate Functions of Port B” on page 69 for a detailed description of how to define the
direction of the user defined SPI pins.
The following code examples show how to initialize the SPI as a Master and how to perform a
simple transmission.
DDR_SPI in the examples must be replaced by the actual Data Direction Register controlling the
SPI pins. DD_MOSI, DD_MISO and DD_SCK must be replaced by the actual data direction bits
for these pins. E.g. if MOSI is placed on pin PB2, replace DD_MOSI with DDB2 and DDR_SPI
with DDRB.
Table 15-1. SPI Pin Overrides
(1)
Pin Direction, Master SPI Direction, Slave SPI
MOSI User Defined Input
MISO Input User Defined
SCK User Defined Input
SS User Defined Input

Atmel ATmega32M1 Specifications

General

Architecture	8-bit AVR
Flash Memory	32 KB
SRAM	2 KB
EEPROM	1 KB
Clock Speed	16 MHz
GPIO Pins	32
I/O Pins	32
ADC Channels	8
ADC Resolution	10-bit
UART	1
USART	1
SPI	1
I2C	1
PWM Channels	6
CAN	1
Operating Voltage	2.7V - 5.5V
Operating Temperature	-40°C to +85°C
Temperature Range	-40°C to +85°C
Package	44-TQFP, 44-QFN