forum.cncdrive.com

This macro makes "smart homing". It homes the axes in the order defined in Configuration/General settings/Homing sequence. The main difference between the default homing and this macro is that you can define backoff for the axes. The other difference is that it handles SoftLimit. When the home position is over the SoftLimit position and SoftLimit is on, then UCCNC will give a SoftLimit error when backing off from the home position, so for the backoff it turns off the SoftLimit.

You have to add to your profile a [SmartHome] section, where you set the parameters. The G28Move<axis>=true/false option enables or disables the backoff move, and the G28Goto<axis>=<coord> value defines the backoff position. Here is a sample:

Code: Select all

[SmartHome]
G28MoveX=true
G28GotoX=0.0
G28MoveY=true
G28GotoY=0.0
G28MoveZ=true
G28GotoZ=45.0

You can call this macro with or without a Q parameter. If you omit parameter Q, then a field will control the homing (see below). If Q exists, then only one axis is homed, where Q=0..5 as X, Y, Z, A, B, C.

I put a field outside of the screen to be invisible, and a slider to control its value in the range of 0..6. 0..5 is the same as parameter Q and 6 means home all: it homes the axes in the order defined in Configuration/General settings/Homing sequence. (The field and slider number is given in SmartHomeAxisFld.) So I have a button and a slider to control which axis to home.


After homing the status looks like this:

I forgot to write that my home switches are on -5 (X and Y) and on 50 (Z), so all axes move 5mm after homing.

Thanks very much Dezsoe.

Keith

I'm having a bit of trouble understanding what I need to add to my profile to add the [SmartHome] section.

I have added the macro to my profile and am able to call it manually. I'm having a bit of trouble adding the field to define the parameters in the macro. Is it just a regular text field linked with the field number 20602?

Field 20602 is needed, because you have to have a numeric field which you can control with a slider. This field will contain a value 0..6, where 0..5 means X to C axis to home, or 6 for home all. If you want only the slider on the screen, then put the numeric field out of the screen (e. g. position 1111,1111).

would be nicer if it would back off to an encoder index pulse

Battwell wrote:would be nicer if it would back off to an encoder index pulse

That's your job on the hardware side to synchronize home switch with the index pulse. Lot of people do it to make homing more precise.

Much appreciated dezsoe

Now that UCCNC has built in backoff settings, is this method no longer needed? Is it the same, better, or worse?

After 1.2101 it's no more needed. The built-in backoff positioning is much faster. It worked fine since 1.2033 (that was the actual version when I wrote it), but now I deleted it from version 2101. It's time for it to retire...