Reading a MAXIM 6675 SPI temperature sensor

The MAXIM 6675 is a chip which can be connected to the SPI bus of the IO-Warrior.
It measures the temperature (needs an extra temperature sensor) from 0 to 1023.75 degrees Celsius.

You need an IO-Warrior with a MAXIM 6675 wired on the breadboard area.
Application note 4 of the IO-Warrior SDK (AN4.pdf) gives more details on that.
Best get the datasheet for the MAX6675 as PDF from http://www.maxim-ic.com

The demo accesses the first IO-Warrior 24 or 56 found expecting it to have the MAXIM 6675 connected.
The IO-Warrior 40 is not able to handle the SPI bus.

Since temperature measurement is slow, the demo uses a 1 sec timer to access the MAXIM 6675.

The main obstacle of implementing the demo is reading and understanding the MAXIM 6675 datasheet.
The chip delivers two bytes of a data word high byte first. The lowest 3 bits are flags.
The rest of the word contains the temperature in 1/4 degree Celsius from 0 degree Celsius upwards.
The value is signed, but is always positive.

Our two test devices (IOWarrior 24 and 56) show the room temperature at 22 and 23 degree Celsius which
is very accurate considered that they use different sensors and that 22 is at only 2 percent of the temperature range.