The uJDM programmer is one of the simplest PIC programmers available. The design comes from the excellent JDM low cost programmer by Jens Dyekjær Madsen. It connects direct to the PC serial port using Windows driver software IC-Prog for easy programming. No external power supply is required  and a simple board layout is given requiring no special PCB manufacture. Note that the design is limited to the PIC16x84 series of chips and cannot be used for In System Programming - ISP. If you need a more advanced programmer then try PPWIN.

Parts

The uJDM circuit connects to the computers serial port through a DB9F female connector. R3 and the LED are optional but are very useful particularly when testing the circuit.

Part list including Maplin Electronics part numbers :-

* Optional components

Building the Programmer

The uJDM programmer is built on VeroBoard 22*13 holes in size. The circuit layout shows the top (left) and bottom (right) side of the board. The copper tracks are cut on the bottom side of the board as shown using a PCB cutter or 3.5mm drill bit. Two 3mm holes are drilled through the board for the DBF9F (J1) connector mounting pins.

Click for high resolution images and photos

The DBF9F serial socket is not on a 0.1" spacing as is the VeroBoard so it is necessary to bend and cut off some of the pins on the underside of the connector as shown.

Solder the components starting with the two connectors to make it easier to locate the smaller components. When complete a useful tip is to use Tipex (white correction pen) on the top center of J2 to mark pin one of the PIC socket. If you also do this on the PICs then you are less likely to plug them in upside-down.

Hardware Testing

I  would strongly recommend that you build the programmer using the VeroBoard layout provided as this will greatly reduce the probability of construction errors. Once you have made the board please follow these simple steps before you start programming.

1. Connect the programmer to the PC serial port using the Female to Male serial lead (K1).
2. Start the IC-Prog software and under 'Settings - Hardware' select JDM Programmer.
3. Insert the PIC into the programming socket.
4. Test the programmer is connected with 'Settings - Hardware Check - Enable Clock' this will allow the power and LED to be turned On or Off. If this does not work check the LED is the correct way round (flat edge to top) and that there are no shorts on the board particularly around the cut tracks.

Links

Links to the latest PIC developments PIC/Ubicom Dev'rs
Jens Dyekjær Madsen JDM low cost programmer
Microchip Home Page