I2C Bus Monitor FAQ (Frequently Asked Questions)

Which I²C Bus Monitor do I need?

We currently offer two I²C Bus monitor/analyzers. Both instruments connect directly to an I²C Bus and other derived busses, and captures, filters, and displays bus activity. The two instruments differ in capabilities, hardware, features, and host computer interfaces. This FAQ will help you decide which monitor/analyzer is right for you.

I2C Bus Monitor Plus

The I²C Bus Monitor Plus (#MIIC-102, Data Sheet, User's Guide) is our most powerful and configurable laboratory grade troubleshooting instrument for the I²C Bus and other derived protocols. When connected to an I²C or derived protocol bus, the I²C Bus Monitor Plus captures, filters, and displays bus message data and timing information.
 

1. Data capture at up to 400K bps (Fast Mode).
2. Filtering of displayed messages by slave address, R/W, Ack/Nack, message data, and SBS violations.
3. Timestamping of each bit, byte, and message with microsecond accuracy.
4. Software selectable I²C Bus signal logic level voltage thresholds (down to 1.8V).
5. High speed host computer interface options (USB, PCI Express, or PCI).
6. Extensive software for message filtering, analysis, logging, and display.
7. Displays SMBus Smart Battery System data in engineering units.

This I²C Bus Monitor Plus uses dedicated hardware technology to collect and deliver bus data to a host PC for logging, analysis, and display. It cannot clock stretch, and is non-intrusive on bus operation.

The I²C Bus Monitor Plus software can operate with, or without, the hardware pod. Use Software-Only mode to exchange message log files with associates.

Recommendation: We recommend the I²C Bus Monitor Plus for traffic intensive I²C Bus, SMBus, or derived protocol applications, 400K bps (Fast Mode) applications, low voltage applications, and applications requiring timing analysis or extensive content filtering.

I2C Bus Monitor

The I²C Bus Monitor (#MIIC-101, Data Sheet, User's Guide) is our most cost effective troubleshooting instrument for I²C Bus and other derived protocols. Operating either hand-held or remotely via a USB or RS-232 serial communication link to a PC, this unit can:

1. Collect bus traffic at up to 100K* bits per second (bps).
2. Filter message data by slave address.
3. Work with bus signal levels down to 3.3 volts.
4. Display bus data on its built-in LCD display.

With the aid of our optional Windows based I2C/SMBus Analysis Software, the I²C Bus Monitor can:

5. Display bus message data on the screen of a host PC.
6. Log captured bus data to a file.
7. Display SMBus Smart Battery System data in engineering units.

*The I²C Bus Monitor uses microprocessor/firmware technology to collect bus data. This technology makes use of I²C Bus clock stretching (holding the SCL line low) during data collection. Clock stretching can slow the bus for up to twelve (12) microseconds during a byte transfer. Since not all bus master devices support clock stretching (wait for the clock stretch to complete), connection of the Bus Monitor to such an "out of specification" systems may cause the system to fail.

Recommendation: We recommend the I²C Bus Monitor for low to middle intensity I²C Bus and derived protocol applications, 100K bps (Standard Mode) applications, 3.3 to 5 volt applications, applications with elevated ground planes, and applications requiring hand-held instrumentation.

Can't find the answer to your question here? Then e-mail your question to us at support@mcc-us.com