I am using a Melzi board with a 12844P chip. I finally loaded the firmware and am getting accurate temperature readings. However, the movement is somewhat buggy. The endstops are triggered and work correctly but the stepper motors are not cooperating. Sometimes entering M commands to move doesn't do anything. Sometimes it drivers the motor and comes to a stop and makes a grinding noise. The z axis doesn't even work normally. If I use ponterface and do micro steps it seems to move.
I think maybe the pin assignment may be out of whack. For example, when I click turn on LED button in ponterface, the external fan hooked up to the boar is turned on. It's weird. Anyway I want to lign up the pins with the correct termination to the Atmega chip; however, the pins.h file does not seem to align correctly with the schematics for the Melzi board.
Here is a snippet:
#define X_STEP_PIN 15
#define X_DIR_PIN 21
#define X_STOP_PIN 18
If you look at the schematics found here :[
reprap.org]
the X-step pin on the MCU is labeled 16X (PCINT31/OC2A/)PD7.
It is riddled with these inconsistencies. It seems that there is no one to one correlation between pin assignment as labeled on the schematics to the ones stated in pins.h
Anyway I'm a noob and don't know much about Arduino setups. It may just be that because I am using a Geeetech Melzi board that I am having all this trouble.
Can someone point me in the right direction? How can I reference the right pin #s
