I know what EPROM is. I just did not realize that under the hood these devices were still UV erasable, especially not for those particular bits. This makes me wonder if you could not apply the same techniques against a large number of ECUs from that era. I'd be very interested in rooting around in those.
The flash in new devices is still erasable with UV (sometimes) but you’ll notice every single chip shown in the video, is a dip package, quite old school.
More modern chips just have metal layers over the flash. You can decap and have a layer of transistors or a layer of metal or some other impediment to the UV light.
Well this guy may have figured out another way to decap chips, this is not a (great) way to hack chips anymore.
I saw an article about some guy that was able to UV erase the metal covered fuses by masking the flash area and lighting the chip at an angle, that allegedly creates a reflection in the metal cover enough to to erase them.
Edit: I found it, http://www.bunniestudios.com/blog/?page_id=40, it's done on a PIC18f1320 which is DIP, it would be interesting to see if there are any changes in the design to mitigate this method.
(I’m a software guy though, so this is all outside my area.)