Autohome

I wonder if someone could tell me how to change the default ‘autohome’ coordinates?

Why would you do that?

Actually you can’t change them as this command moves the axis towards the end-stops.
The only thing you can change is the value of the coordinates (at the end-stop the value is 200 for X and Y). If you define a lower value your bed will be considered smaller or wider if you select a higher value.

The coordinates are in ‘configuration.h’ of the firmware:

// Travel limits after homing #define X_MAX_POS 200 #define X_MIN_POS 0 #define Y_MAX_POS 200 #define Y_MIN_POS 20 #define Z_MAX_POS 190 #define Z_MIN_POS 0

Thank you for your help raby. Could you please clarify the following for me?

From the two statement;
#define X_MAX_POS 200
#define X_MIN_POS 0

The auto home position is assigned the value 200 and the position at the end of travel is assigned the value 0. This means that the maximum length of travel is 200mm, i.e., the difference between the maximum and minimum assigned numbers. If this is correct then if one was to change the MAX value to 180 and left the MIN at 0 then the maximum travel to the left would now be 180mm. If on the other hand one changed the MIN value to 20 and left the MAX value at 200 then would the effect be exactly the same as 200 minus 0 would also equal 180?

I think you got it right. The numbers aren’t important only the difference between max and min is.
In the home position the max value is assumed and you’re allowed to move the axis until it reaches the min value.

Thank you for that. If you don’t mind I will post later on what I think I have to do to upload these changes and may be you could correct any errors that I have made.

Thank again