ESP8266 Community Forum

- Tue Sep 02, 2014 5:05 pm #123

wouldn't wrtiting to the flash require a small application running on the controller transferring the received bytes to the connected flash controller?
aka flash loader?

That is one way.

Another way is for the JTAG to take over the pins on the ESP8266 and then wiggle them appropriately to program the flash chip.

Where I get my modules

- Tue Sep 02, 2014 5:08 pm #124

Mind you: it's not an arm; it's an Xtensa architecture proc. There also seems to be an openocd-variant for that, though.

The hardware in those ARM JTAGs should be ok, but the software will not be. You will need an Xtensa version of OpenOCD. But I think that already exists. Almost all of those ARM JTAGs have an FTDI FT2232 chip in side of them.

Where I get my modules

- Thu Sep 04, 2014 2:28 am #153

Mind you: it's not an arm; it's an Xtensa architecture proc. There also seems to be an openocd-variant for that, though.

The hardware in those ARM JTAGs should be ok, but the software will not be. You will need an Xtensa version of OpenOCD. But I think that already exists. Almost all of those ARM JTAGs have an FTDI FT2232 chip in side of them.

Ah, sorry, I thought you mentioned somewhere the chip has an arm core, but I must have misread. Agreed, jtag inteface cables can be used interchangebly between architrectures.

- Wed Sep 24, 2014 6:34 pm #893 Kind of a newbie on the start from nothing trail. I have an ESP-01 and am wondering where I would connect the JTAG. I have not found that documentation anywhere. This forum has been a tremendous help as far as getting an IDE up and running and the xtensa OCD, but if I had the correct JTAG, how would I connect it without a microscope. I may be missing something.