Sanguinololu and RAMPS homing in different ways?

Hey guys, not a problem, but a question. Something I want to change on my RAMPS, but can't find out how to do.

On my Sanguinololu (using Marlin) whenever I hit home when everything is already homed, all axis move away a few mm from their endstops and look for home again. I find this rather useful.
On my RAMPS (using Marlin) whenever I hit home when everything is already homed, nothing happens. This is because the machine thinks because the endstops are triggered, that it is at home. I find this annoying.

I want my RAMPS machine to look for home every time I want to. So, when it's already at home, I want it to move away from home and look for home again.
I have tried several search queries for homing differences between RAMPS and Sanguinololu, but all I find is 'help me my printer is not homing' topics.

Does anyone know what I can do to change this behavior? It would be great if my RAMPS would unhome itself before it homes.
Also, it would be great if this could work with the LCD panel.

I have found this:

//homing hits the endstop, then retracts by this distance, before it tries to slowly bump again:
#define X_HOME_RETRACT_MM 5 
#define Y_HOME_RETRACT_MM 5 
#define Z_HOME_RETRACT_MM 1

However, it is active, and doesn't seem to do anything. Apparently.


As time moves fast, I seem to have found out the problem...
[github.com]

After months of searching haha, and now I open a topic and within 5 minutes of opening the topic, I find the solution.
Good morning!
- Marinus

Edited 2 time(s). Last edit at 05/06/2014 11:04AM by Ohmarinus.

The homing strategy is entirely in the realm of the firmware, not matter which hardware it operates on.

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Generation 7 Electronics	Teacup Firmware	RepRap DIY

Quote
Traumflug
The homing strategy is entirely in the realm of the firmware, not matter which hardware it operates on.

Well, I am not sure about that. My RAMPS and Sanguinololu are both using the exact same version of Marlin.

On my Sanguinololu machine, the homing retraction works out of the box, and on the RAMPS it doesn't. Probably because the pin assignments are different. So, in a way, yeah, in the software domain, but it's also a result of the electronics being different I guess.

OK, I mean with properly configured Pins both times.

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Generation 7 Electronics	Teacup Firmware	RepRap DIY

My Marlin setup re-tests the endstops even when homed, you might want to try a fresh firmware.