The TWI-bus can be used to request information from the EDBG. This is done by sending
a special sequence as described below.
The sequence starts by sending a normal start condition followed by an address byte (default
address is 0x28) with the RW bit cleared. Then a request token identifying the requested
information is sent. Normally, a received byte would be put into the DGI buffer, but a
repeated start will trigger the EDBG to parse the received token. Then an address with the
RW bit set. The EDBG will then start to push the requested data onto the TWI-bus. All response
bytes must be ACKed by the master, and the final byte must be NAKed.