The lock bits are not programmed from our factory, they are in the erased state. Unlike the user array, the SB, BV, and lockbits erase to zeros. Its their erased/ programmed state that is important here. Atmel copied Philips on the Rx2 flash parts (and added EEPROM). Philips parts have always had PSEN low when you come out of reset to enter ISP mode. But, on both Philips and Atmel, you MUST have the correct BV value for it to work. The issue here is what happens if the BV was corrupted.