Fundamentally, the use of pull-ups to set a logic one limits the maximum speed of the bus. This
may be a limiting factor for many applications. This is why the 3.4 Mbps high speed mode was
introduced. Prior to using this mode, the bus master must issue a specific ‘High Speed Master’
code at a lower speed mode (for example: 400 kbps Fast Mode) (refer to Table 1), which initiates
a session at 3.4 Mbps. Specific I/O buffers must also be used to let the bus to shorten the signals
rise time and increase the bus speed. The protocol is also somewhat adapted in such a way that
no arbitration is performed during the high speed transfer. Refer to the I²C specification for more
information about the high speed mode.