Has anyone found a 128kword compatible USBASP?

[Phil_G]

I'm looking at the ATMega2560
https://www.ebay.co.uk/itm/Arduino-Mega ... 2729181876



...but my usbasps are Baite locked ones which dont do extended addressing, which of course with ATTinys and 328P's isnt a problem. Has anyone found a source of a USBASP loaded with software version 1.5 having the extended addressing please? I'm a bit reluctant to try updating a USBASP with another one as I fear I'd just brick both though I do have the ATmega8 v1.5 hex file.

While some USBASP ads claim to be ATMega2560 compatible, they seem to be using an old "pre-extended addessing" version of Fischl so I dont know if you can believe them

Cheers
Phil

[Mike_K]

Hi Phil

I had this problem a few years back when I was trying DIY OpenTx with an Arduino ATMega2560. I used a Hobbyking USBASP that is now discontinued, but any USBASP that has a "self program" header is easier, otherwise you'll be soldering links to the reset pin. And the latest firmware on https://www.fischl.de/ didn't work reliably for me, but I followed the advice on the following link and got it sorted out using:

https://openrcforums.com/forum/viewtopi ... 363#p29615

I assume firmware V1.5 is the same as the one in the above link? The good news is that if you do brick the USBASP they only cost a few pounds and I doubt you'll brick it. There is next to no chance that you'll brick the one you are using to update the other one with, you are just programming another ATMega after all.

And don't forget you can just use the ATMega2560 USB bootloader, with 256K memory, losing a couple of K isn't really a big deal for most projects. Out of interest what project are you using it for? 256K is a lot of memory when we're used to 32K with a 328P or 8K with an ATtiny85!

Mike

[Phil_G]

An update: I bought two identical new USBASPs, the common LC Technology ones that use the atmega8.
This was so I had two identical ones and there was no risk of me trashing my 'working' usbasps.
I updated one with the other, then reversed the two so both are now updated to v1.5
It was a piece of cake, took 2 or 3 minutes max

As a bonus it also gets rid of the 'cannot set sck period' warning, which is nice

This is the sequence I used (I found the online examples dont work directly):

First, blow 'blinky' into a Nano via the icsp header just to prove the new usbasps actually work.
Fit the J2 link to the target usbasp, then connect the two usbasps with the supplied ribbon cable.

Copy the attached hex file to the avrdude location, which is:
C:\Program Files (x86)\Arduino\hardware\tools\avr\bin

Rename it from "usbaspv15.hex.gz" to "usbaspv15.hex" ie remove the ".gz" bit from the end
(the .gz is just to fool the forum as hex files arent allowed as attachments)

Open a DOS window (start, run, Cmd) and change to your usbasp directory:
cd \Program Files (x86)\Arduino\hardware\tools\avr\bin

Save the existing usbasp flash (just in case):
avrdude -C "C:\Program Files (x86)\Arduino\hardware\tools\avr/etc/avrdude.conf" -c usbasp -p atmega8 -U flash:r:flash-usbasp.bin:r

Write new v1.5 update file to usbasp flash:
avrdude -C "C:\Program Files (x86)\Arduino\hardware\tools\avr/etc/avrdude.conf" -c usbasp -p atmega8 -U flash:w:usbaspv15.hex

Thats it, easy peasy. Wheres my atmega2560 ? ah yes, the slow boat...

Out of interest what project are you using it for?

I dunno Mike, I just like the sound of 16 analogues maybe a 10S battery monitor for my ebike.
Maybe some encoder ideas, or maybe I'll load blink then put it away...

Edit: the 2560 has arrived, its a bit bigger than I expected (about three prominis) , but when you're holding 16 analogues and fifty-odd digitals in your fingers its most impressive. Tried a few things and it does everything you ask!
A bonus is that the bootloader delay is negligable, maybe 200ms so its quick enough for me and I'll probably favour USB programming after all!