search

makerbot / ReplicatorG

An open-source gcode interpreter for driving RepRaps, Makerbots, and other similar CNC beasties
http://replicat.org
GNU General Public License v2.0
404 stars 226 forks source link

When writing to file, set a default zero position #72

Closed makerbot closed 14 years ago

makerbot commented 14 years ago

If there's no G92 code at the start of a build, when it writes to file the interpreter may do some goofy offset. The virtual machine needs to have a default position (probably zero).

ssd2 commented 14 years ago

I think I've noticed this bug.

The control panel has a sane offset first time it is opened -- possibly read from the makerbot.

Why does it need a default position at all, especially if the first command in the file tells the makerbot just to go somewhere. The firmware seems to initialize itself to zero, but if it already knows where it is, code sent to it should use that and not reset it.

I've generated some strange s3g files by using print to file. I wish I had a s3g to gcode translator (can replicatorg do this?) to find out what it put in the file!

makerbot commented 14 years ago

Often with problems like this, I'm struggling between fixing an issue and not producing unexpected behaviors for those who have trained themselves to work around it. :P

s3g->gcode shouldn't be too difficult to implement, but I'd do it as a standalone python script instead of part of ReplicatorG. It's probably a two hour project.

ssd2 commented 14 years ago

I don't think anyone expects the machine to go insane and set its position to X3289 Y5042 if it doesn't have a G92 at the top of the file. I'm not sure what expected behavior you expect fixing this bug to break.

The behavior I'd expect is that gcode files that don't reset the position at the beginning work the same if I print them live as if I print them to an s3g file and print from sd card. This use to work...

phooky commented 14 years ago

Assumes a start position of 0,0,0 when generating a file.