Schaer+ Programmer
Description
Schaer is a generic programmer circuit capable of uploading and downloading firmware to/from several electronic devices like microcontrollers and eeproms. This and other programmers came to my attention when I was working in CAMBADA, the robotic soccer team from the University of Aveiro, and since all other programmers available there were too expensive for me to buy or build, I decided to build one that was simple and cheap!
This programmer has given me lots of trouble with high capacity PICs and I decided to cancel the project and build a ICD2 clone for MPLAB. What rests here are just the remains of the project.
Design and Implementation
I can't remember where I found the first schematic on the web but after testing it in a white board I decided it was best to try a definitive solution on a PCB. The circuit is very straightforward: it gets its control signals from the parallel port and sends it to the PIC being programmed. It needs one power supply of at least 15V and generates its 13V and 5V with 78XX regulators.
Schematic
It's a direct copy of the schematic found on the web and the prototype white board.
PCB
Most of the tracks are on the bottom layer. Only three are at the top layer and can be made using wire jumps.
Software
This programmer can be used with icprog.
Evaluation
While using it for almost 4 years I decided to go to something more reliable like an ICD2 clone. This circuit always gave me mixed results when programming some 32KB flash PICs.
Downloads
Nothing here.
References