[avrdude-dev] at90usb162 problem after erase

[Brad Schick]

I am running the 5.6 release of avrdude on linux, using a jtagice mk II
in isp mode to program an at90usb162. I am finding that after performing
a chip erase, further operations work either fail or malfunction. For
example if I just erase the chip with:

>./avrdude -p at90usb162 -c jtag2isp -P usb -e -v

I get output like this:

...
avrdude: Device signature = 0x1e9482
avrdude: safemode: lfuse reads as BF
avrdude: safemode: hfuse reads as D8
avrdude: safemode: efuse reads as FC
avrdude: erasing chip

avrdude: safemode: lfuse reads as FE
avrdude: safemode: hfuse reads as 0
avrdude: safemode: efuse reads as FE
...

The fuses read after the erase are wrong (even though each is read 3
times). If I run the following command next, I can see that the fuses
are actually fine.

>./avrdude -p at90usb162 -c jtag2isp -P usb -v

...
avrdude: Device signature = 0x1e9482
avrdude: safemode: lfuse reads as BF
avrdude: safemode: hfuse reads as D8
avrdude: safemode: efuse reads as FC

avrdude: safemode: lfuse reads as BF
avrdude: safemode: hfuse reads as D8
avrdude: safemode: efuse reads as FC
avrdude: safemode: Fuses OK
...

Writing flash also fails if I allow the auto-erase step to happen. But
if I first erase manually, then disable the auto-erase with -D the write
works.

Does the at90usb162 just needs to be reset after an erase? I am running
avrdude in a debugger, and if anyone has suggestions I can help track
down the issue.

-Brad