Usb CncPlayer	Usb CncPlayer	Usb CncPlayer
There is an interesting Usb controller board family available on the market called Arduino. I choose the Arduino Duemilanove, aka 2k9 and ordered some equipment and spare parts.	In order to make the handling of the board a bit more convenient I also ordered a piggy-back board which is called a shield in the Arduino terminology. I thought having a board with screw terminal would be nice.	The shield comes as a kit and I had to assemble and solder it which is a pretty easy task.

Usb CncPlayer	Usb CncPlayer	Usb CncPlayer
This is the controller board and attached on top is the shield with the screw terminal. As you can see it is pretty small. The microprocessor board itself comes fully assembled so nothing to do here. The board is equipped with an Atmel AVR ATmega328p microprocessor.	Same image but I rotated the board a little bit. On the left you can see the Usb connector. The board is powered simply by usb cable. No need to deal with an external power supply (but can be used optional).	Now it's getting a bit weird. On the Arduino board is a small reset button but once you put the shield on top you can't operate it any longer because the button is fully covered.

Usb CncPlayer	Usb CncPlayer	Usb CncPlayer
So what to do? There are several solutions but I opted for a pure mechanical one. I drilled a 6 mm hole in the shield, used a 2.5 mm nail and a spare part from a bycicle's front brake. It looks like a M6 bolt but got a 3 mm drilled hole inside. On a bike this bolt is used to adjust the lash or tension of the front brake's Bowden cable.	The difficult part was to drill the 6 mm hole at the very right position. Surprisingly everything fitted perfectly. I just had to cut off the nail and grind it a little bit. The reset button extender doesn't look very well but works like a charm. Design follows function ;)	Here we are almost done. This is my custom tailored test equipment for the moment. The board's controller has a bootloader. This means that programming the firmware is simply done via the usb cable. No external programmer/burner is required. The wires seen in the image still need to be connected to the shield. Instead of plugging the cnc machine into the PC's lpt port the cnc machine is now plugged into this 25 pin connector.

• So what is this all about? Well, I'm going to port the CncPlayer Client Cpc software to this usb microcontroller which I will call Usb CncPlayer.
• Can I buy the Usb CncPlayer? No, because the firmware is still under development. I estimate that only 40% of the programming work is done as of today. So 60% of the work is still ahead of me.
• Do I need the Usb CncPlayer hardware for the CncPlayer software? No. This board is just a future optional accessory.
• I already bought the CncPlayer software. Can I upgrade my version once the Usb CncPlayer is available? Yes. I'll offer an inexpensive upgrade plan.
• When will the Usb CncPlayer board be available? Frankly, I have no idea at the moment because I'm still in an early development stage.
• Do you use the Arduino ide for programming? No. I use the Atmel AVR studio and a C compiler. The Arduino ide is great but I wanted to have the firmware code to be as portable as possible. Maybe later I'll replace the Duemilanove board by a board with more I/O and more RAM or switch over to a PIC. Not yet sure where it will end.
• How many I/O got the Arduino Duemilanove? 14. That means we can have XYZC stepper motors = 4 * 2 = 8 pins. Then 4 homing switches = 4 pins. And finally one pin for spindle and one pin for coolant = 2 pins. So 8 + 4 + 2 makes 14 pins total. That's almost the same what a PC's lpt port offers and that's pretty well for most hobbyist's cnc job needs. You can also redefine unused pins, btw.

New CncPlayer Projects:

Project 1: Support for external USB Cnc Controller

I intend (and some small parts are already implemented) to support the following controller with the CncPlayer. The list order is random and got no meaning:

These 3 images show the DeskCnc controller (no. 1 in the above list) which an user mounted on a board. Please note that the controller is pretty small. Thanks to R. for the images:

Project 2: Retrofitting / turning an old A3 flat bed plotter into a sign cutting plotter

A3 refers to the German paper size A3 which is about 420 mm x 297 mm (ca. 16.5 inch x 11.5 inch). The plotter's electronic can't handle today's software protocols like Hpgl etc. That means you can't use that plotter in an today's computer environment. So I want to remove the electronic and substitute it by an ordinary external stepper motor electronic and control it with the CncPlayer. At least this is what I intend. I'm curious if it will work that way.

The great thing of these old plotters is that they are comparatively big, comparatively solid and very cheap because most owner can't use it (due to the outdated protocol and connector). For low-budget cnc user such devices are a great deal to get a lot of mechanics for little money.

More information on my plotter project will follow (depends on the progress I'll make).