regarding spi communication

I'm new to arduino. I wanted to access the scl1 and sda1 for SPI communication with Max6675 to measure the temperature using K type thermocouple. how to access scl1 and sda1 since they dont have any digital pin no. I'm used to Uno not to due. Along with it , can the Chip select pin be used on any digital pin? Suggestions are welcome.

As per datasheet, I can see that Max6675 communicates via SPI as a Slave (not I2C !!) with a microcontroller as an SPI Master.

Or you can read it like it is done in this thread:
http://forum.arduino.cc/index.php?topic=19963.0

ard_newbie:
As per datasheet, I can see that Max6675 communicates via SPI as a Slave (not I2C !!) with a microcontroller as an SPI Master.

Or you can read it like it is done in this thread:
MAX6675 Thermocouple Interface - Interfacing - Arduino Forum

cant we use the sda and scl for spi? Sorry to ask if its wrong. SPI also uses clock and data signal for communication, can we use normal digital pins for spi communication. If so then sda and spi pins are particularly for i2c communication. Is there any special pins for spi communication?I see six pins in centre of due as SPI what does it is used for?

Yes the 6 pins in the middle of the Due are the SPI pins. Note that the power pin there is 5V even though all the other pins are 3.3V and you must use one of the regular pins elsewhere for the CS signal.

You can use software SPI on any pin but that's almost never necessary so you won't find a lot of information about that.

The DUE chip has USART as well as UART. Any USART port can also be used as an SPI but once again, you will have to dig past the first page of Google results to get anything useful.

The letters SDA and SCL are specific to I2C communications. Don't get I2C and SPI confused.