Hi all,
I want to measure the temperature of Pt100 elements and the temperature of thermocouple both parallel on a Arduino Mega 2560 Rev3.
I have multiple Adafruit MAX31865 (Adafruit PT100 RTD Temperature Sensor Amplifier - MAX31865 : ID 3328 : $14.95 : Adafruit Industries, Unique & fun DIY electronics and kits) to measure the temperature of the Pt100 and a Playing with Fusion MAX31856 with T-Type thermocouples
(Playing With Fusion - 4-Channel J-Type Thermocouple MAX31856 SPI Digital Arduino Shield).
If I use multiple Adafruit MAX31865 with the programmable SPI Pins 50,51,52 everything works fine.
If I connect the Playing with fusion board on the Mega everything works as it should. But if I connect only the pins GND, 3.3V and IOREF, as well as the pins CS0 to CS4 and the three main SPI pins SDO, SCK, SDI it works depending on how I connect the main SPI pins of Playing with fusion to the mega (see image), I go from Playing with fusion to the arduino:
works: main SPI pins => cable => ICSP
works sometimes: main SPI pins => cable => 50,51,52
does not work( gets really strange numbers): Main SPI pins => cable => Breadboard => cable => ICSP
does not work: Main SPI pins => cable => Breadboard => cable => 50,51,52
So my questions are:
What is the difference between ICSP and the software SPI pins 50,51,52 in this use case?
How can I connect both devices probably so I can use them on the mega in parallel?
When the first question is solved:
I have seen the Playing with fusion (Mode 3) and Adafruit (Mode 1) use different SPI modes. Is there a way to switch between the modes?
Thank you very much in advance for your time and help!
Cheers Paul
