The 83XXX Flash block is divided into two sections, block0 and block1. Now put the black box in the block0. When you switch to the block1, the black box will not be used.Should the black box program also have its counterpart in Block1?Or do you call the black box program in a public section?
I suppose you mean the flash programming mechanism, there is Flash memory Module(FTFE), it's register address is located at the X:1c7xx, with the register operation, you can erase/program the block0 and block1.
This is the part of FTFE register.
If I misunderstand you, I am sorry.