Dallas DS1650Y & GQ-4X write problem

[MetalHead]

Hi guys!

I try to move content from old DALLAS DS1650Y chip to the new one for my Tektronix TDS520A scope and
I can't do this with GQ-4X programmer. DS1650Y is in a list of supported devices.
Reading operation went fine, but when try to to write buffer into nvram chip it fails with this
error message.



Does anybody know what I'm doing wrong. Maybe chip is somehow write protected? I tried different speeds no way... (