Okay folks. It's 2016 now and christmas time is over. That means it's project time!
My raspberryPi software which I started earlier was developed for the RaspberryPi 1. Now I struggled with some small issues why I changed my mind. I will now use the raspberryPI 2.
Here are the reasons:
- RaspberryPi one has not so much I/O pins. For producing a raspberryPi-only laser cutter controller without external port multiplexers Pi one is enough if you don't want to configure micro stepping.
- RaspberryPi two is a "normal" computer. That means one can install any linux distribution like debian or ubuntu without any problems.
- I decided to use objective C / swift as development language, because it's a really elegant language and available on debian and ubuntu. It's compatible to C, C++ and objective C. That means I can recycle a lot of my ready made code.
- RaspberryPi 2 is using multiple CPU kernels. That means that dispatch queues and multithreading are working nice.
- I will use DMA and direct access to the I/O ports. This makes it possible to control the motors without using a realtime kernel. I just want to make it able to completely run the whole thing on an ordinary raspberryPi with a standard distribution!
Please be patient. There is still a lot of work to be done. In February I will move the laser cutter to the workshop of Digitales Aachen e.V. where I will do the testing and development of the software.
After a long time of thinking about G-Code I now decided to drop it. All G-Code generators I have found on the network are ugly. The results are not smooth enough, a lot of post processing is necessary. The G-Code is not a real standard which means that every machine treats g-code differently.
This project should be a laser cutter. The best thing for laser cutters is vector graphics. The best tools for vector graphics I have seen so far are Affinity Designer, Illustrator and Inkscape. All these tools are able to export svg vector format.
My goal is now to read and interpret real svg files. There will be some restrictions at the beginning, but svg seems to be the right format for laser cutters. G-Code for me is deprecatedwhy I won't use it anymore.