PICStep

Fixed the issues with the Version 3.1 PICStep design. Now have incorporated the status LED's onto the opto-isolated breakout board instead.

New breakout board is dual layer (sorry!) for ease of design. I plan to get some professionally made along with a few of the V3.1 PICStep's

To see the changes look at the top of this page!

Due to me stupidly testing this Version 3.0 design with an opto-isolated breakout you may be suffer damage to your parallel port cause by the status LED's drawing to much power with the 270ohm drop resistors. I'm going to modify the design to include some form of buffer driver to stop this problem. Until I rework the PCB design please don't build these boards. The V2.1 boards are identical plus the ICSP and minus the status LED's

After much feedback I've re-done the boards again! This time no ICSP socket and DIP switches, a few status LEDs for Step, Direction, Brake, CoilA Dir, and CoilB Dir. This update should make for a slightly neater board with even less wire links! :)

I've written some simply assembly instructions and a few notes on using PICStep in a text file you can download.

After having so many people build these boards I thought it fitting to have a little gallery of their hard work. You can see the gallery here.

Plus also a very big thank you to Terry, Shaun, Bill and others for their generous PayPal contributions! You can contribute too by clicking on the little PayPal icon (man I'm starting to sound like dan@dansdata.com :)!

View the gallery!

A minor bug fix has been released. The latest is now PICStep V1.01

Thanks to Bob Weiss for pointing out my error. The previous version of the firmware has a small bug that doesn't effect the usage of PICStep, but is incorrect code. In the main loop I used a "call" instead of a "goto" for a few check routines. So what will happen is the 8 position call stack would overflow but causing no harm to the operation. This bug doesn't cause/do anything it's mostly cosmetic and thankfully has now been fixed. Update if you want to, but the previous version still works just fine.

I took a small webcam video of PICStep driving a 24inch linear stepper motor. Once I figured out how much current I could push through the coils the motor actually is quite strong. I would make an awesome x-axis in a gantry type CNC drilling machine/vinyl cutter as it's mechanical resolution running in 1/8th step mode is quite something (with no possible backlash!). It's fun to think what I'm going to do with this thing!

A few small modifications to the existing V2.0 board. Basically just a few cosmetic changes like the addition of mounting holes (again!), removable of some redundant wire-links, and a slightly better routing of the ground. Otherwise it's exactly the same design, just on a slightly bigger PCB.

PICStep V1.0 firmware has been released! (Yippie!)

It now is fully functional on a PIC16F628A and includes some nice new tasty features!

New features include :-

• Automatic motor shutdown after around 6 minutes of inactivity (saves your motors from burning when your job is finished)
• Watchdog timer automatic reset (the controller will now automatically reset itself after 18ms if the PIC crashes)
• More optimized table look ups and interrupt handling (hopefully should yeild more RPM!)

Finally finished the PICStep PC interface board. It has an on-board 5v regulated supply, emergency stop / motor enable screw terminal, expansion header for three more PC outputs and five PC inputs (all with screw terminals).

It doesn't offer opto-isolation or anything fancy, so use a parallel port PCI card if you don't trust your wiring (or my designs :)