1-15
IM 701450-51E
I
2
C Bus Signal Analysis Function
1
Examples of Setting the Trigger Conditions of the I
2
C Bus Signal
This section will indicate the data sequence in bytes (hexadecimal notation) and indicate
the position where the trigger will occur. The symbols used in the figures are as follows:
S:
Start condition
Sr:
Restart condition
P:
Stop condition
Shaded area:
Byte pattern to be compared
Non-ACK Trigger
A trigger is activated when the Acknowledge bit is not present (when the SDA signal is
set to “H”).
...
...
SDA
SCL
Start condition
1 2 3 4 5 6 7 8 9
A R/W bit
Acknowledge bit
Data byte
Trigger activated here
1 2 3 4 5 6 7 8 9
Acknowledge present (L)
Acknowledge not present (H)
Stop condition
Note
The Non-Ack trigger does not apply to start byte and Hs mode master code.
Address & Data Trigger
• Activate a Trigger Only on the Start Condition
Trigger Condition
Address Pattern:
Not applicable
Data 1 Pattern:
Not applicable
Condition:
True
Data 2 Pattern:
Not applicable
Condition:
True
Ignore the Restart Condition:
No
Ignore Unexpected Start/Stop Condition:
No
<Byte Count=0>
S
25
AE
57
27
FE
98
99
27
P
A4
A R/W bit
Trigger activated here
<Byte Count=3>
S
25
AE
57
27
FE
98
99
27
P
A4
2. Trigger activated here
1. Skip 3 bytes
A R/W bit
1.4 Setting the I
2
C Bus Signal Acquisition Conditions
