OpenServo.com

ginge · Posted: Thu Apr 27, 2006 6:14 pm Post subject: TWI bootloader magic addr

Hi,

I am programming by openservo code using the TWI bootloader, and have one problem.

After flashing the AVR, the docs suggest reading or writing to the magic address of 0xFFFF to load and execute the application code.

I have tried reading, and writing to the magic address, without any results.

Can anybody confirm that read/write to the magic address actually boots the application code, or am I just doing it wrong.

Barry

mpthompson · Joined: 02 Jan 2006 Posts: 650 Location: San Carlos, CA

Barry, I looked into this and it appears the small piece of code in the ATtinyX5 bootloader (twi.c line 165) didn't make it into the ATmega version of the bootloader during the conversion process.

I'll fix this tonight and post an updated version of the bootloader. Thus far I've been exiting the bootloader by cycling power on the v2.1 servos so I missed finding this myself. Sorry about that.

-Mike

ginge · Posted: Thu Apr 27, 2006 10:51 pm Post subject:

please, don't apologise!

These things happen, good work tracking it down.

Barry

mpthompson · Joined: 02 Jan 2006 Posts: 650 Location: San Carlos, CA

I added the single line of code in twi.c at line 183 to cause the bootloader to exit if the magic address of 0xffff is referenced. This reminds me that I'll need to working on the bootloader enhancements that have been discussed over the last month or so.

I didn't get a chance to test this change, but I'm pretty sure it should work. I'll test it in the next day or so.

-Mike