What happens to update latches and data/instruction registers of the boundary scan circuitry when the device enters the Test-Logic-Reset state? Are they set or reset?
When the device enters the Test-Logic-Reset state, the BYPASS instruction becomes the current instruction; hence, the instruction register and update latches are set (output High).
The 1-bit BYPASS register is selected by the BYPASS instruction. You may shift out the data in this register by performing the shift-DR instruction.