I'm having some trouble setting the BATLOWEN bit. I find that I get the expected default value of 0x25F8 for OpConfig when I read registers 0x3A and 0x3B. When I try to set the BATLOWEN bit (bit 2) and read the results back though, the contents remain unchanged.
This is the sequence of operations that I'm using:
Write 0x00 to register 0x00 // Unseal the memory
Write 0x80 to register 0x01
Write 0x00 to register 0x00 again
Write 0x80 to register 0x01 again
Write 0xFC to register 0x3B
Write 0x20 to register 0x00 // Reseal the memory
Write 0x00 to register 0x01