User manual

PicoScope 6 User's Guide 181
Copyright © 2007-2013 Pico Technology Ltd. All rights reserved. psw.en r32
9.6.3
I²C protocol
You can decode I
2
C Bus data using the serial decoding feature built into PicoScope.
About I
2
C Bus
I
2
C (Inter-Integrated Circuit) Bus is a serial protocol used mainly in consumer
electronics for communications between devices on the same circuit board, and
between computers and displays. The standard was originally developed in the 1980s
by Philips. It uses two signals: clock (SCL) and data (SDA).
The in-window view of the data looks like this:
The columns in the data table are as follows:
Column
Description
No.
Serial number of the packet (decimal). If Accumulate mode is
off, this counts from the start of the selected waveform. If
Accumulate mode is on, this counts from the start of the first
waveform in the waveform buffer.
Packet
Packet type: Start, Stop, Address, Data or Unknown.
Address
Shown for address packets.
Read/Write
Polarity of the Read/Write flag.
Data bytes
Contents of data packets.
Acknowledge
Whether the destination acknowledged the packet.
Baud Rate*
The signaling rate detected for this packet.
Start Time
Time according to PicoScope timebase at start of frame.
End Time
Time according to PicoScope timebase at end of frame.
Packet Time*
The duration of the packet (End Time – Start Time).
Min Voltage*
Minimum voltage.
Max Voltage*
Maximum voltage.
Voltage Delta*
Voltage range of the signal (Max Voltage – Min Voltage).
* Display of these items is toggled on and off by the Statistics button.