invalid signature on devduino sensor node

I was playing with a devduino sensor node
I had it connected with ISP connection to another arduino programmed as Arduino ISP
all was good, i had various sketches and so on, then i tried to put their alternative boot loader (1mhz 1.8v), it flashed successfully, if i remember correctly i tried another 2 sketches, then the he said that the programmer was not responding, since sometimes when the IDE fails the only way is rebooting i rebooted the mac, now if i try to re upload the boot loader or the sketch (with upload with programmer" i get the "invalid device signature"

is there a way to know if the chip has failed? is there a way to recover? why has it happened?
the onboard chip is a 238p-au

Thank you!

It may be that the 1MHz clock rate is too slow for Arduino as ISP to work properly. You need an ISP programmer that will support slow clock rates.

This is very similar to another thread about programming an attiny13 at 1MHz.

The TinyISP sketch works just like Arduino as ISP but supports slow clock rates. Try it and see if it helps.

One other thing is anything else connected to the DevDuino when programming? You should remove other modules before programming and see if that helps also.

I tried TinyIsp, i also tried to add the default_bitclock = 10; in the avrdude.conf but nothing changed, i always get the invalid device signature error :frowning:
Can i see what signature it sends? i am not even sure it sends anything.
I have an old analog oscilloscope, is there a "send pin" i can monitor during the loading to see if it even responds, or to see if it is alive?
Yes i have removed the wireless module and the sensor node has no other hardware attached.

here is the extension to the boards.txt, i have it on mac so i had to make some modifications to make it work (int1MHz, 1.8V)






One other thing is how is it being powered when programming via ISP? If they are running at different power level 5V and 3.3V then it's possible the chip is damaged. The programmer and the Devduino should be at the same power levels when programming.

Since the wireless module is 3.3V i was powering it with 3.3V also when the wireless module was removed (lazy) if i power it at 5V i get another error, "Expected signature for ATMEGA328P is 1e 95 0F Double check chip, or use -F to override this check."

I really can't remember what i have done the last time it worked, however i always was using ISP connector, is there a difference if you program a chip (not boatload) with ISP or serial?
Is it safe to upload a sketch via serial using 3.3v power and 5v signal on tx? (i imagine rx is 3.3v wham receiving from 3.3v powered atmega.)

You should not be using two different power levels that can cause damage. They should be both at 3.3V when programming or uploading. Or they can both be at 5V when programming or uploading. Never mixed.

You can try programming at 5V with the battery removed and see if that works.

I always program devices with only one power source, if the device is already powered and is a trouble to disconnect (rare) i only connect tx-rx and ground, (or isp and ground without power on the isp connector) but if i can, i disconnect main power and go with the usb2serial or arduino as isp, the problem maybe was that my usb2serial (original officine arduino made) has a different pinout than the sensor node, witch is identical to the luigino board, so i made an adapter from usb2serial to luigino/sensornode, and i made with an onboard 3.3V converter and switch so i can use it to power and monitor serial also when the wireless module or other 3.3v only module is installed.
This led to the 5v signal and 3.3v power mix during boot loading.

So now probably it is broken, is it?
Maybe it’s time to experiment with my heat gun and try to put there a new atmega?