PICStep

After many requests, here is a parts list of the PICStep V2.0 boards including part no. for Jaycar, Dontronics and DigiKey.

Resistors
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5 x 10K 1/4W (R5, R6, R7, R8, R9)                       RR-0596
2 x 20K 1/4W (R1, R3)                                   RR-0603
2 x 20K 1/4W (R2, R4) - Adjustable to set current limit

Capacitors
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2 x 2.2nF MKT (C1, C3)                                  RM-7022
2 x 500pF Ceramic (C2, C4)                              RC-5333
2 x 1uF 100V MKT (C5, C7)                               RM-7170

Last night I knocked together another PICStep board, but this time using the professionally produced boards. The results speak for themselves!

They went together excellently! I only stuffed up a few hole sizes in the design (namely the 10 pin IDC should be 1mm not 0.8mm, and the 100uF electro should also be 1mm not 0.8mm), but apart from that it all went together like magic.

While building this board I took photos of each step and I plan to put together some basic building instructions and a complete parts list.

A FedEx parcel landed on my desk and inside contained 12 fresh new professionally produced PICStep V2.0 boards!!!

The quality is awesome (I know it's just a single layer board and all, but I'm excited okay.. :P ) and I got a good price too. CustomPCB.com did an awesome job, and got them to Australia in under 5 business days too!

I've also just received a few more LMD18245's too, so I'll be constructing a couple of these boards to try out. If you'd like to purchase some of said boards they'll be $22 inc GST each.

Again with the late nights, but not because of PICStep. I came home from a late meeting (11pm) and didn't feel ready for bed, so I took some photos and some crappy webcam footage of the PICStep running via TurboCNC.

You can see my current setting resistors sitting high above the board in their sockets because I haven't trimmed them down to the sockets while I'm still fiddling. You just pop in a new set of 1/4W resistors to set the maximum current of the driver (resistor = 20,000 / max coil current eg. 20000/0.7A = ~27K) and the LMD's take care of the rest!

Late last night in my little computer room PICStep breathed life into a small step-motor. At first triggered by a debounce push button, PICStep happily stepped the motor step by step in all modes. After a little more frigg'n around I hooked PICStep up to a parallel port, increased the drive current up to 1.5A and the drive voltage to 34V, then connected up a higher powered motor, and then started up TurboCNC on my test PC. And voila! Full microstepping action!!!

Finally! I'd found some time this weekend to dedicate to actually producing some PICStep boards and finally get to test it properly with hardware. After a few stuff ups with the press-n-peel transfer film (man I never thought this stuff was that fussy till now) I finally got the designs onto the boards and etched. Tonight I sat and painstakingly drilled all the holes, then mounted the numerous wire-links till finally all the components where on the board. Now I've just got to test it out before I apply full load to it. I'll do this during the week.

A total re-design of the PCB to make it more friendly to Press-n-Peel laser printer transfer film. I tried the V1.3 board with the film and I produced a few boards but some of the tracks are to small and the etching has made them fairly marginal in use. So I decided to start again and use thicker PCB traces. This should also allow the board now to be milled with a moderately accurate PCB mill.

I've changed the PCB design a little, moved the input IDC connector, removed the +5V screw terminals in favour of the IDC, added a few more filter caps and just generally tidied up the board. Gerber/RS-274X and EPS files have been updated above to reflect the changes. Gonna start building these soon!

I've updated the schematic to reflect the updated 8 to 10pin IDC, plus I've added all the values to the diagram. R2 and R4 are changeable to set the require maximum current it driver can supply (should never go below 6.8K else you'll kill the drivers)

Cleaned up and adjusted the design slightly plus I added mounting holes! I've made sure there is enough distance between traces and changed the input connector from an 8 pin IDC to a 10 pin so that I can use the locking IDC connectors I already have. :)