BAT32G1x9 user manual | Chapter 20 Serial interface IICA
766 / 1149
Rev.1.02
20.5.13
Wake-up function
This is a subordinate function of I
2
C, which is the function of generating an interrupt request signal
(INTIICAn) when the local station address and extension code are received. The processing efficiency is
improved by not generating unwanted INTIICAn signals under different addresses. If a start condition is
detected, it enters wake-up standby. Because the master device (where a start condition has already been
generated) may also become a slave due to a arbitration failure, it enters wake-up standby at the same time
as the address is sent.
To use the wake function in deep sleep mode, you must place the WUPn at "1". The address can be
received independent of the operating clock. Even in this case, an interrupt request signal (INTIICAn) is
generated when the local station address and extension code are received. After this interrupt is
generated, the WUPn bit is cleared to "0" by the instruction and returned to the usual run.
The flow when the WUPn position "1" is shown in Figure 20-20WUPn position "0" is matched by address
matching is shown in Figure 20-21shown.
Figure 20-20 the process when the WUPn position "1" is placed
START
MSTSn=STDn=EXCn=COIn=0?
No
WUPn=1
wait for 3 fMCK clocks
wait
execute deep sleep instruction.
Yes