MKS-Base problem and solution for two extruders...
My original printer build used a RAMPS clone main board called an MKS-Base v1.2
This is supposed to be a RAMPs1.4 system on a single board.
It worked well using RAMPS in the firmware config (board #33)
However when I went to add a second extruder things went wrong. Activating the second extruder heater produced a high whining sound.
Looking at the board I noticed the LED for the FET controlling the print cooling fan came on but dimly while the LED for the heater did not light.
A little messing around and I felt like their must be a short in the board or a miss connection, the whine came from the fan trying to run
but at too low of a duty cycle. Removing the Fan from the configuration allowed the FAN LED to go full bright when the heater turned on.
I decided the board must be defective so I ordered a replacement..now at ver 1.5
Of course the replacement did exactly the same thing....so now I suspected the Firmware. As it turns out I think there is something wrong in the PINS header file and the second heater and the print cooling fan seem to map to the same pin. I made a small change "see below" and now it all works. Not sure if this is specific to the MKS boards or is a general problem but if it is just the board then maybe adding a new board to the configurator would be a better solution.
// uncomment one of the following lines for RAMPS v1.3 or v1.0, comment both for v1.2 or 1.1
// #define RAMPS_V_1_3
// #define RAMPS_V_1_0
#ifdef RAMPS_V_1_3
#define ORIG_X_STEP_PIN 54
#define ORIG_X_DIR_PIN 55
#define ORIG_X_ENABLE_PIN 38
#define ORIG_X_MIN_PIN 3
#define ORIG_X_MAX_PIN 2
#define ORIG_Y_STEP_PIN 60
#define ORIG_Y_DIR_PIN 61
#define ORIG_Y_ENABLE_PIN 56
#define ORIG_Y_MIN_PIN 14
#define ORIG_Y_MAX_PIN 15
#define ORIG_Z_STEP_PIN 46
#define ORIG_Z_DIR_PIN 48
#define ORIG_Z_ENABLE_PIN 62
#define ORIG_Z_MIN_PIN 18
#define ORIG_Z_MAX_PIN 19
#define ORIG_E0_STEP_PIN 26
#define ORIG_E0_DIR_PIN 28
#define ORIG_E0_ENABLE_PIN 24
#define ORIG_E1_STEP_PIN 36
#define ORIG_E1_DIR_PIN 34
#define ORIG_E1_ENABLE_PIN 30
#define SDPOWER -1
#define SDSS 53
#define ORIG_SDCARDDETECT 49
#define LED_PIN 13
#define ORIG_FAN_PIN 9
#define ORIG_PS_ON_PIN 12
#define HEATER_0_PIN 10
#define HEATER_1_PIN 8
#define HEATER_2_PIN 7 //Was pin 9 changed for MKS-BASE
// ANALOG NUMBERING
#define TEMP_0_PIN 13
#define TEMP_1_PIN 14
#define TEMP_2_PIN 15
#define E0_PINS ORIG_E0_STEP_PIN,ORIG_E0_DIR_PIN,ORIG_E0_ENABLE_PIN,
#define E1_PINS ORIG_E1_STEP_PIN,ORIG_E1_DIR_PIN,ORIG_E1_ENABLE_PIN,
Comments
I have overwritten all possible ifdefs, so this will only work with an EFBE configuation.