Thermocoupler K type - fault

CJ.BRAVO

Hey there.

Just got a K type thermcoupler and a MAX31856 (adafruit).

not sure where to connect the CS pin to the NPCS0 on the DUET 2 (WIFI) ...

config is :

M305 P2 X150 T"K"

M563 P2 H2

thanks

CJ.BRAVO

the Duet guide shows chart of the MAX31855... is it the same for the MAX31856 ?

A Former User

On the duet side the SPI connection would be the same, which the CS is a part of. If its the same between the two Maxim chips you'll find in their datasheets.

CJ.BRAVO

this is from the adafruit sheet:

SPI Logic pins:
All pins going into the breakout have level shifting circuitry to make them 3-5V logic level safe.
Use whatever logic level is on Vin!

SCK - This is the SPI Clock pin, its an input to the chip
SDO - this is the Serial Data Out / Master In Slave Out pin, for data sent from the MAX31856 to your processor
SDI - this is the Serial Data In / Master Out Slave In pin, for data sent from your processor to the MAX31856
CS - this is the Chip Select pin, drop it low to start an SPI transaction. Its an input to the chip

I got it connected as instructed but still reads 2000c.

CJ.BRAVO

OK. so its works. here's the chart for the MAX31856 (adafruit):

Vin --> +3.3V
Gnd --> Gnd
SCK --> SPIO_SCK
SDO --> SPIO_MISO
SDI -->SPIO_MOSI
CS--> SPIO CS0-CS2

Also, there isn't CS1 on the duet board so CS2 on the board is actually X151 on the config.

I suggest adding this to the Duet guide and also dis-mention that you can buy the duet daughter boards on the website (I didn't see any there).

Thanks!

dc42

Thermocouple daughter board on Duet3D web site https://www.duet3d.com/DuetAddons/TC_K_DaughterBoard

CJ.BRAVO

@dc42

when clicking "ORDER" on the homepage you only get the control boards.

If you scroll down on an individual product you see related products with more items to purchase - not so accessible that way. missing out other duet products...

dc42

On the Order page you have to go to "Touch Screens, IR Probes, PT100 sensors, e3d products and more!" and click on that link.

CJ.BRAVO

@dc42

gotcha