TK3 PICKit2 adapter

EPE Magazine, Toolkit Mk 3 PICKIT/ICD adapter

Current Status: Complete
Date:                29th February 2008
License:             Creative Commons Attribution 3.0 Unported License


Introduction

This page describes how to make a simple adaptor to use the Microchip PICKit 2 with the EPE Toolkit MK3 dev board.

Note: I will never provide schematics for the EPE Toolkit MK3 PCB or associated artworks, they are copyrighted items.

Background

The author uses the EPE Toolkit MK3 (commonly known as TK3) development board for programming and testing PIC micro controller circuits. The software provided with the board and available to download from the web, allows you to program a number of devices but for many reasons, it does not support some of the newer PIC microcontrollers.

Microchip have released the PICKit 2 programmer and debugger, which is available for under 30/$60/45 Euro which supports a number of devices and works with USB ports. It also allows you to debug your software using MPLAB.

You can also power the TK3 PCB directly from the PICKit 2 when programming.

How to connect a PICKit 2 to the TK3 PCB

On the TK3 PCB, there is a header for In Circuit System Programming (ICSP) which can be used to program a target board, the relevant connector is shown here, click to enlarge.

pcb_showing_header_TN

The connections between the PICKit 2 and TK3 PCB are quite simple. The PICKit 2 has the following pinout, taken from the user manual:

Pickit2_pinout

To connect it to the TK3 PCB you need to swap a few signals over:

interconnect

Note: click on the thumbnail pictures to enlarge.

To do this I used a bit of veroboard and some appropriate pin headers. On my board, I used turned pin sockets as that was easier to poke wires into. So to connect this adaptor board, I used the double ended turned pin socket shown on the left in this picture.
Click to enlarge

I used two 2mm bolts and some nuts to take the weight of the PICKit 2 adaptor, you will see why later on. The piece of veroboard I used was 7 rows by 10 holes and looks like this:

adaptor_topside_TN  adaptor_underside_TN

The pin header for the PICKit 2 is bent slightly upwards to clear the bolts used to provide mechanical strength.

The finished adaptor simply plugs into the TK3 PCB as shown, and the PICKit 2 plugs in.

Pluggedin_final_TN 

Testing the Adaptor

To test adaptor, I loaded up the PICKit 2 programmer application and run the Troubleshooting utility, accessible from Tools-> Troubleshoot menu item. This brings up a dialogue box that guides you through  the steps to ensure that the right signals goto the right places. All you need is a multimeter to check voltages.

Troubleshooting

Optional modifications to the TK3 PCB.

 During testing of designs on the TK3 system, I have observed up to 150 mV of power supply ripple on the TK3 +5V power rail. To reduce this, fit 100nF decoupling capacitors across the power pins of every PIC socket as shown here (Click to enlarge). This brought the noise down to around 50mV, when running at 20 MHz.

decoupling_mod_TN

Conclusion

The TK3 PCB is a useful, low cost board for developing PIC microcontroller applications. With this simple adaptor, the usefulness of the board is increased by not only gaining support for programming a number of new devices but you can also debug your design using MPLAB.

Updated 08 July 2017