Saturday, 6 December 2014

USB Programmer for 93c46 family EEPROMs

I have seen many people have been searching for a At93c46 programmer. Some time ago i built a programmer for one of my friend. So here i am publishing its source and schematic. 

I built the programmer using ATTINY2313 AVR micro-controller. My programmer uses V-USB library to implement a software based USB protocol handler.

If you want the high-resolution PDF format of the schematic here it is.

I have implemented the programmer using the USI module found in the ATTINY. However there where couple of glitches which came up when interfacing with same chip from different manufacturers. Solution for it is provided in the Host Software.

The USI module of Tiny2313 is configured to run as SPI Master mode 0.

The Source code for the programmer can be found at

If you want only the at93c46 interfacing library then you will only need at93c46.h and at93c46.c files from the repository.

The companion windows software is at

Just enter the program name in the console and press Enter it will show all the commands that are valid.

I built the circuit and fit it into a small transparent case. This is what my final design looks like:

Since I designed the programmer circuit on a perfboard(DOT PCB). So i can't provide any board layouts. But you are welcome to make your own designs. Click here to download the schematic in .sch format.

Until now i have only added support for the c46 chip with 1KBit, but in future i may add support for c56, c66 and other members of the family. Meanwhile if any you are interested to add support for other chips, then just grab the source and modify as you like.

If you have any suggestions or question you can post a comment.
Unknown An Electronics and Tech Enthusiast

I am a Tech enthusiast who loves to build stuff like new gadgets and tinker around with electronic devices doing some DIY stuff, writing some code and in the process providing something back to the community.


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