Using M140 to assign multiple heaters as one bed

ComedianTF2

Hi All,

I'm trying to create a single bed heater in the DWC that utilises multiple heating units. It seems that the M140 gcode is unable to use multiple heaters, unlike the M563 command.

For example, the following code only shows 1 heater in the DWC, but works properly for the tool heaters

M308 S0 P"e0temp" Y"thermistor" T100000 B4725 
M308 S1 P"e1temp" Y"thermistor" T100000 B4725	
M950 H0 C"duex.e2heat" Q500 T0
M950 H1 C"duex.e3heat" Q500 T1
M143 H0 S120
M143 H1 S120

M140 H0:H1 P0


M308 S3 P"spi.cs1" Y"rtd-max31865"    
M308 S4 P"spi.cs2" Y"rtd-max31865"      
M950 H3 C"e0heat" T3    
M950 H4 C"e1heat" T4    
M143 H3 S500
M143 H4 S500

M563 P0 D0 H3:4 S"test dual heater"

As you can see, the tool heaters use heater 3 and 4, while the bed heater only uses heater 0.

From what I can gather, it seems that M140 is unable to use multiple heaters in the same way that the M563 can use it.

Edit: This is on RepRapFirmware 3.4.1

Phaedrux

@comediantf2 said in Using M140 to assign multiple heaters as one bed:

From what I can gather, it seems that M140 is unable to use multiple heaters in the same way that the M563 can use it.

Correct. You can't combine bed heaters in that way. The current usage would have you create multiple independent bed heaters with M140 P and then you would need to control the temperature of the heaters using the same P value to target the heater.

ComedianTF2

@phaedrux Thanks for the confirmation