e-licktronic Forum

edit: the problem was originally that the wrong eeprom was in the bom, thats updated now. The input problem was a broken trace and is now fixed.

original post below


Vincent said i should post here so that it may help others once its resolved.

Anyway built my nava, voices test ok but the sequencer had problems.

It would enter run/edit mode, I was able to edit last step, edit steps etc mode, running tempo led with control everything but no chase light running. After checking over the soldering I was thinking it may be a problem with the eprom since initialization didn't solve it, i removed the eprom and powered up to see if there was a behaviour change. A this point it got stuck in a loop where some buttons would work and the tempo clock is still running, but not much else. Replacing the eprom and now I can no no longer initialise it.

I've just tried to use the boot loader and a sysex but now my nava is bricked, i can re enter sysex mode but not much more. i have an ispII here, so possibly a hex would fix it....(if i had one)

adjusted the sysex speed and was able to get back in, however its back to the saved bugged state. Currently stuck in edit mode, keys 1-8 change patterns a0-a7, start flashes, as does the selected pattern and the pattern edit button.

So it would seem that the last state was saved when there was no eprom loaded, so i may be in a bug trap of sort

an update, the ISP header has the MOSI and MISO pins swapped, after making an adaptor I was able to reflash the firmware. Code verified written but still stuck in the same crashed loop where nothing but 8 pattern buttons work. My best guess now is the boot loader is corrupted since i can not access the trim or eprom init procedures at boot time.

we suspect this may have been caused by the eeprom being the wrong type, the BOM has been updated

EDIT 5/18/16
Important update! On semiconductor EEprom does not seems to work with current firmware so you need the Microchip one
-On semiconductor CAT24M01 EEprom replace by Micropchip 24LC1025

Great work on troubleshooting!
Is the Microship EEPROM verified to work?

i have new parts arriving today, we shall see. Its possible one of the registers may be faulty also, as i have now reflashed the boot loader, will report back once we have some progress.

replaced the button registers and some buttons are alive again, its quite possible this is a fault with a via or something along those lines, the entire voice set works over midi.

nava rocking the house, all fixed, nothing to see here

https://www.instagram.com/p/BFmmxXIxz6y ... by=dinsync

I'm glad to hear that you fixed your problem, that has to be a relief. Not that I'm happy you had this issue but it sure will save some time and aggravation now that we know the proper EEprom (On semiconductor CAT24M01 EEprom) to order. I placed my mouser order 2 weeks ago but I wasn't having them ship it until all the components were in stock on 6/21. Now I just have to have them change that one part for me and I should be good to go. It sucks being the guinea pig but I'm happy for you now.

housedet@comcast.net wrote:I'm glad to hear that you fixed your problem, that has to be a relief. Not that I'm happy you had this issue but it sure will save some time and aggravation now that we know the proper EEprom (On semiconductor CAT24M01 EEprom) to order. I placed my mouser order 2 weeks ago but I wasn't having them ship it until all the components were in stock on 6/21. Now I just have to have them change that one part for me and I should be good to go. It sucks being the guinea pig but I'm happy for you now.

thanks, there was quite a bit of head scratching as it didn't make any logical sense but we got there in the end.