Ramps 1.4 D8 and D9 linked?

Hello, finished assembling my MP3DP yesterday with a Ramps 1.4 board. I uploaded the Ramps 1.4 EFB firmware, connected the bed to D8, extruder fan to D9 and extruder heater to D10. When I turn on the fan manually with M106, the heatbed warms up slightly. When I turn the heatbed on with Pronterface, the extruder fan turns on. I Googled this and really can’t find anything that would explain this behaviour. I doubled checked the code in Marlin for pins_ramps.h, mostly this:

#define HEATER_0_PIN RAMPS_D10_PIN

#if ENABLED(IS_RAMPS_EFB) // Hotend, Fan, Bed
#define HEATER_BED_PIN RAMPS_D8_PIN
#elif ENABLED(IS_RAMPS_EEF) // Hotend, Hotend, Fan
#define HEATER_1_PIN RAMPS_D9_PIN
#elif ENABLED(IS_RAMPS_EEB) // Hotend, Hotend, Bed
#define HEATER_1_PIN RAMPS_D9_PIN
#define HEATER_BED_PIN RAMPS_D8_PIN
#elif ENABLED(IS_RAMPS_EFF) // Hotend, Fan, Fan
#define FAN1_PIN RAMPS_D8_PIN
#elif DISABLED(IS_RAMPS_SF) // Not Spindle, Fan (i.e., “EFBF” or “EFBE”)
#define HEATER_BED_PIN RAMPS_D8_PIN
#if HOTENDS == 1
#define FAN1_PIN MOSFET_D_PIN
#else
#define HEATER_1_PIN MOSFET_D_PIN
#endif
#endif

#ifndef FAN_PIN
#if ENABLED(IS_RAMPS_EFB) || ENABLED(IS_RAMPS_EFF) // Hotend, Fan, Bed or Hotend, Fan, Fan
#define FAN_PIN RAMPS_D9_PIN
#elif ENABLED(IS_RAMPS_EEF) || ENABLED(IS_RAMPS_SF) // Hotend, Hotend, Fan or Spindle, Fan
#define FAN_PIN RAMPS_D8_PIN
#elif ENABLED(IS_RAMPS_EEB) // Hotend, Hotend, Bed
#define FAN_PIN 4 // IO pin. Buffer needed
#else // Non-specific are “EFB” (i.e., “EFBF” or “EFBE”)
#define FAN_PIN RAMPS_D9_PIN
#endif
#endif

 

Would anyone have an idea of what the problem may be?

There are a few flavors of Ramps to flash, you chose EFB=extruder fan bed, sounds like you want EBF. I am not sure of the exact name but I think that is it. Look at the boards list or my ramps firmware to see what we used.

Or just swap the bed and fan wires.

To clarify, these are concurrent. Should have read as

When I turn on the fan manually with M106, the heatbed warms up slightly as well as the fan spinning. When I turn the heatbed on with Pronterface, the heatbed heats up and the extruder fan turns on.

Ohhhh, I can only assume that is a bad board, have a look at the mosfet solder joints, maybe they are bridged. Other than that try my firmware and see if the same thing happens.

1 Like

Might also be a grounding problem, where one or more of the outputs are using the other to back ground.

1 Like

Two mosfets were touching each other, works fine now.

1 Like