Shopbot Code VS G-Code?

[rb99]

What is the difference between Shopbot code and G-Code?

Are there any advantages / disadvantages to either?

Can a Shopbot take straight G-Code?

Thanks,

RB

[drodda]

Shopbot code is very different than G-code. There is a conversion from shopbot code to g-code but you can't run a shopbot with straight G-code.

[zeykr]

The later versions of shopbot control software will run gcode. Output a g code file from vectric or whatever you use to create files ( I used g-code arcs (inch) (*.tap) and then put shopbot in preview mode and do a File/Part file load, then choose g code files from the file type drop down.

Shopbot code and g code are quite similar in function but the names are changed to make them easier to understand for the user -- a G0 x,y,z is the same thing as shopbots M3 x,y,z. It's pretty easy to remember shopbots M command is a move, but remembering what a g0, g2, g23 etc is is harder for those that don't use it all the time.

[garyb]

Just a little correction Ken, a G1 x,y,z is the same as M x,y,z,
GO is a rapid move (jog)
Like you said numbers can be hard to remember at times!

[rb99]

What is the difference between running Shopbot and Mach 3?

[bill.young]

Richard,

There are a lot of dialects of g-code...this wiki article lists the g-code commands that the ShopBot software understands.

http://shopbotwiki.com/index.php?title=GCodeMain

Bill

[zeykr]

oops!

Then G0 = J3, G1 = M3

[dana_swift]

G Code is defined by a standard: "RS-274D". The problem is that RS-274D was not created to control machine tools, it was created to control photo plotters. It got "pressed into service", using only the "G" command section of the spec for the new application.

You can get a copy of RS-274D online for free. Just try reading it if you are having trouble sleeping.

G Codes are only one part of RS-274D, there are P codes, X codes, M codes, N codes, etc. When you actually read the spec it makes sense when you realize that the intent was to drive film plotters not machine tools. That got cobbled in later.

So the CNC industry has standardized on a control language about as appropriate to the purpose as pig-Latin. Because G codes are not clearly defined for CNC application no two companies use them exactly the same way. Some of the codes are obvious and used uniformly, but get into something esoteric such as turning on and off some auxiliary function and there is no commonality at all.

Shopbot avoided most of the mess by defining their own control language, very well suited to controlling shopbots. Mere humans can quickly learn to read (and write) the code. I can read most of it without referring to any manual. Though some of the parameters for complex commands like arcs, I don't remember all the parameters and options.

If you have a choice between G and SBP files, try using SBP, you will probably have less trouble.

Then if you are interested in challenges, try writing some RS-274D files that are widely compatible with a variety of machines. Let us know if you have success. Its nearly guaranteed with SBP files.

Hope that was not an unwelcome tutorial.

FYI I don't dislike RS-274D, it is a wonderful thing in other industries that use photo-plot CNC, such as PCB manufacturing. I just like SBP files for controlling the bot.

D

[joe]

Dans,

Have you ever been interested in Mach 3? It's a dreamboat. Unfortunately it's not compatable with SB code.

Since we are almost neighbors, feel free to come by at anytime. I have an open shop and welcome anyone with or without a CNC.

Joe

[dana_swift]

Joe- I have seen Mach 3, but never had call to use it. Do you have to replace the control board or re-flash its control program in the bot to use it? Or does it communicate using the existing SB communications protocol? I presume you use Mach 3 instead of SB3.

So far SB3 has been just fine for my use, especially since I have written my own tool path generation software. I wrote an interface to the new communications mechanism (which is "unimpressive") so I can communicate to the level that SB3 allows. If Mach 3 can communicate to the controller in the bot, then so can I, it will just require some reverse engineering I have been avoiding, but is easily done.

Thanks for the invite, that day will come no doubt, I get up to the Norman area from time to time. Likewise, I'm just at the other end of the turnpike! Consider the welcome mat to be out!

With just a few minutes notice I can even brew up a fresh pot of caffeinated beverage..

D