Building Atmel programmer yourself?

Projects Programming
1

I saw some Atmel chip programmers on eBay, for low prices, small USB modules.

So if I start off writing my own programming software, it would be only for fun/experience purpose.

I started off a few months ago to design and build a PIC flash writer, having full tristate control, generating correct programming voltage, having a 32k RAM buffer, small LCD, control LEDs, relay for the supply voltage...

I tested it a little already, the tristate works correct, I can set the level to 0 or 1, or floating, or Vpp (programming voltage). Unfortunately, no schematics exist :slight_smile:

Then I had the idea, this circuit could also be used to program for instance ATMEGA8.

Some larger ATMEGA chips have JTAG, the ATMEGA8 actually does not. I have read it yesterday in the datasheets.

How much effort is it to implement the software for a flash writer?
I could use Visual Studio if I wanted to, and the PCB has RS232 interface.
The MCU is a PIC16f884.

ICSP_programmer.jpg
ICSP_programmer.jpg1024×646 167 KB

2

You may get your answer if you read about avrdude.

3

If you have an Arduino you already have the necesary hardware for a programmer. Would be real easy to get hold of a 328 and make a dedicated programmer. I built a small board that I hook to my Arduino and program 328 and tiny2313 chips using it.

There already exists the ArduinoISP sketch so it would just be a matter of figuring out whether you want a shield or a dedicated board to do the programming.

4

Adafruit sell a shield, but it's no big deal to hook up the six or so wires needed to get from your Arduino to your chip.

However it sounds like you are doing your own. You don't need JTAG, just the SPI interface.