Stripboard JDM PIC Programmer

JDM PIC Programmer

Note: This is a preliminary design and has not yet been tested

Introduction

This is based on the original JDM programmer design. The original design requires either a PCB or fiddly fabrication on plain perforated board. The design outlined here uses the same stripboard methods as suggested for other modules and is simpler to build.

This programmer is only required for bootstrapping a machine (see RepStrap), as the complete machine will include it's own PIC Programmer.

Requirements

Components

• R1: 10kΩ
• R2: 1.5kΩ
• C2: 100μF electrolytic capacitor (25V or more)
• C3: 22μF 16V or 47μF 6.3V tantalum capacitor
• D2: 5.1V zener diode (0.5W or more)
• D3: 1N4148
• D4: 1N4148
• D5: 1N4148
• D6: 8.2V zener diode (0.5W or more)
• D7: 1N4148
• Q1: BC547B NPN transistor
• Q2: BC547B NPN transistor
• An 18 pin IC socket

Schematic

Making the board

Board connections

• J1 - Serial connector

1. 1. TxD
   2. GND
   3. CTS
   4. DTR
   5. RTS

• J2 - Mode selection

1. 1. Common
   2. For old PICs
   3. For new PICs including 16F628 (for RepRap projects)

If you're planning of programming a variety of PICs, you should connect J2 to a switch so you can easily switch configurations. If you're only planning on programming PICs for the RepRap project, you can just hardwire pin 1 to pin 3 with a jumper (and leave pin 2 disconnected).

Usually you will be connecting a cable from the programmer to a 9-pin serial connector for plugging into a PC. Use a female 9-pin connector. Wire J1 as follows

1. TxD to pin 3 (on the 9 pin connector).
2. GND to pin 5
3. CTS to pin 8
4. DTR to pin 4
5. RTS to pin 7

Variations

The 1N4148 diodes may be replaced with 1N4448 or other equivalent diodes if more readily available.

D5 and D7 may be replaced by a BC557B. Emitter to MCLR and Collector to Vss.

See Also

• RepStrap

-- Main.SimonMcAuliffe - 11 Mar 2006