CMS32L051 User Manual |Chapter 14 Serial interface IICA
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14.5.6 Wait
Wait to notify the other party that the master or slave device is preparing for the send/receive of data
(waiting status).
By setting the SCLAn pin low, the other party is notified that it is waiting. If both the master and
slave wait states are released, the next transfer can begin.
Figure 14-19 Wait (1/2)
(1) The case where the master device waits for 9 clocks and the slave device waits for 8 clocks
(Master device: send, slave device: receive, ACKEn=1).
enter into wait state
after output 9th
Clock.
write data into IICAn (release
from wait).
master device resume
Hi-Z state, slave device
stays in wait state (low
voltage)
slave device waits master device waits
H
IICAn
SCLAn
SCLAn
IICAn
ACKEn
SCLAn
SDAAn
transmis
sion line
slave
device
master
device
IICAnFFH or WRELn1
enter into wait state after
output 8th Clock.