How to JTAG with Arduino?

Projects Programming
1

I've been doing alot of work on my phone.... Way too much to go into here.

Anyways.. I'm about to brick my phone while testing something. I need to use JTAG to bring my phone back to life. Does anyone know of some code that can run on an ATMega to perform JTAG uploading of a firmware?

2

What Arduino version do you have? Uno or older?

3

I think usually you'll need your JTAG to emulate some particular JTAG dongle supported by the host-side software for un-bricking/programming/whatever. And the chances that an arduino can emulate that particular JTAG programmer are rather slim :frowning: (as far as I can tell, JTAG is a big lie. They went and implemented a supposedly generic, hw-independent, multi-vendor standard for manipulating hardware, only to simply move the proprietary bits to different levels of the communications hierarchy. Roughly equivalent to "our MSDOS-running computer has a different graphics interface than the IBM PC, and we're not going to tell you how to use it." Grr. I'd love to be proven wrong, though.

4

The Altera USB Blaster is a FT232 based design (not to be confused with FT2232), if he had a non-UNO version, he might be able to hack it, the USB Blaster is supported by OpenOCD

5 
"our MSDOS-running computer has a different graphics interface than the IBM PC, and we're not going to tell you how to use it."

Showing your age...... :wink:

6

frank26080115:
What Arduino version do you have? Uno or older?

I have an ATMega. 1280 I think. I know JTAG should be possible with the wiring library. If it can be done with a slow paralell port, it has to be possible with an 18mhz Arduino. JTAG is possible. I just need a library or program to use.

I have the data and a memory location to write. I just need an interface to write it with. JTAG works. All I need is a program for the Arduino. I don't have a paralell port on my computer, or it would be pretty easy.