iPort FAQ (Frequently Asked Questions)

Which I2C Bus Host Adapter is right for me?

We currently offer six versions of our I2C Bus Host Adapter. All these adapters interface a host computer to an I2C Bus, but with different capabilities, hardware, features, and host computer interfaces (ASCII or Windows DLL, USB or RS-232). This FAQ will help you decide which adapter is right for you, including free software, custom programming considerations, and our application recommendations. If you need more help, send your questions to us at support@mcc-us.com.

Table of Contents:


iPort/USB (USB Interface with ASCII Fast Mode)

The iPort/USB (#MIIC-204, Data Sheet, User's Guide) USB to I2C Host Adapter is a popular addition to our I2C Bus host adapter family. With its simple ASCII text command and Virtual RS-232 Communications Port interface, the iPort/USB is designed to work with any Windows 98SE or above based host computer with an internal or self-powered external USB port.

The iPort/USB can be an I2C Bus master or slave device. As a slave, the iPort/USB can respond to a user selected slave address and the I2C General Call address (0x00). As a master, the iPort/USB supports multi-master operations, arbitration detection, clock-stretching by a slave device, and the optional /INTerrupt signal found on some I2C devices. Enhanced features include I2C Bus mastering at 23, 86, 100, or 400 kHz Bit Rates, 12 Mbit/second USB interface speeds, USB bus-powered with optional power for I2C Bus devices, and eXtended commands for low-level access to I2C signals making it compatible with many "I2C-like" devices. The iPort/USB also has a fast processor, 256 byte data buffers, and firmware optimization. Based upon a Philips Semiconductor microcontroller, the iPort/USB provides our best implementation of I2C Bus technology, and is fully licensed by Philips to use their technology.

The iPort/USB includes two (2) free Windows applications (Message Manager and Message Center) that help you get started sending and receiving I2C Bus messages quickly. You can also use terminal emulation software like Windows Hyperterminal, or write your own custom program in Microsoft VB, VB.NET, C, C++, C++.NET, C#, Delphi Pascal, National Instrument LabVIEW, and more. We even provide free Sample Programs to help you get started.

Custom Programming: The iPort/USB provides an ASCII command and Virtual RS-232 Communications Port interface to a Windows host computer. An application program sends simple ASCII text commands out the virtual RS-232 serial port to set up the adapter and send or receive I2C Bus messages. Because the iPort/USB includes a virtual RS-232 interface, it is backward compatible with software applications written for our iPort/AFM or iPort/AI host adapters. LabVIEW developers can take advantage of our Virtual Instrument Driver Library.

Recommendation: We recommend our iPort/USB for I2C Bus traffic intensive applications, and for users who want to write custom Windows application programs. The ASCII command and Virtual RS-232 Communications Port interface of the iPort/USB makes it easier to interface with almost any application program development tool.


iPort/AFM (ASCII Fast Mode)

The iPort/AFM (#MIIC-203, Data Sheet, User's Guide) RS-232 to I2C Host Adapter is our most powerful and fastest I2C Bus host adapter. With its simple ASCII text command interface, the iPort/AFM is designed to work with any computer with an RS-232 serial port.

The iPort/AFM can be a bus master or slave. As a slave, the iPort/AFM can respond to a user selected slave address and the I2C General Call address (0x00). The iPort/AFM supports multi-master operations, arbitration detection, clock-stretching by a slave device, and the optional /INTerrupt signal found on some I2C devices. Enhanced features include I2C Bus mastering at 23, 86, 100, or 400 kHz Bit Rates, RS-232 baud rates of 19,200, 57,600, or 115,200, and eXtended commands for low-level access to I2C signals making it compatible with many "I2C-like" devices. The iPort/AFM also has a fast processor, larger data buffers, and firmware optimization. Based upon a Philips Semiconductor microcontroller, the iPort/AFM provides our best implementation of I2C Bus technology, and is fully licensed to use this technology.

The iPort/AFM includes two (2) Windows applications (Message Manager and Message Center) that help you get started sending and receiving I2C Bus messages quickly. You can also use terminal emulation software like Windows Hyperterminal, or write your own custom program in VB, C, C++, Delphi, LabVIEW and more. We even provide free Sample Programs to help you get started.

Custom Programming: The iPort/AFM provides an ASCII command interface to the host computer. An application program sends simple ASCII text commands out the RS-232 serial port to set up the adapter and send or receive I2C Bus messages. Because the iPort/AFM does not use a DLL, it is compatible with DOS, UNIX, Linux, Windows, and any other OS that supports a serial port. If you need to add an I2C port to a Single Board Computer, embedded microprocessor, or microcontroller, the iPort/AFM is designed for you. LabVIEW developers can take advantage of our Virtual Instrument Driver Library.

Recommendation: We recommend our iPort/AFM for I2C Bus traffic intensive applications, for users who want to write custom application programs using Microsoft's Visual Basic or National Instrument's LabVIEW, and for non-Windows based host computers. The ASCII command interface of the iPort/AFM makes it easier to interface with almost any application program development tool.



iPort/AI (ASCII Interface)

The iPort/AI (#MIIC-202, Data Sheet, User's Guide) RS-232 to I2C Host Adapter is designed to work with any computer with an RS-232 serial port. With its simple ASCII text command interface, the iPort/AI is designed to work with any computer with an RS-232 serial port.

The iPort/AI can be a bus master or slave, and supports multi-master operation, arbitration detection, and clock-stretching by a slave device. The iPort/AI supports I2C Bus mastering at 100 kHz, and RS-232 baud rate of 19,200. Based upon a Philips Semiconductor microcontroller, the iPort/AI provides an industry proven implementation of I2C Bus technology, and is fully licensed to use this technology.

The iPort/AI includes two (2) Windows applications (Message Manager and Message Center) that help you get started sending and receiving I2C Bus messages quickly. You can also use terminal emulation software like Windows Hyperterminal, or write your own custom program in VB, C, C++, Delphi, LabVIEW and more. We even provide free Sample Programs to help you get started.

Custom Programming: The iPort/AI provides an ASCII command interface to the host computer. An application program sends simple ASCII text commands out the RS-232 serial port to set up the adapter and send or receive I2C Bus messages. Because the iPort/AI does not use a DLL, it is compatible with DOS, UNIX, Linux, Windows, any other OS that supports a serial port. It works with Single Board Computers, and even embedded microprocessors or microcontrollers with an RS-232 serial port. LabVIEW developers can take advantage of our Virtual Instrument Driver Library.

Recommendation: We recommend our iPort/AI for less data intensive applications, for users who want to write custom application programs using Microsoft Visual Basic or National Instrument LabView, and for non-Windows based host computers. The ASCII command interface of the iPort/AI makes it easier to interface with almost any application program development tool.


iPort (Windows DLL Interface)

The iPort (#MIIC-201, Data Sheet, User's Guide) Windows to I2C Host Adapter is designed to work with Windows based PCs. Based on a Windows DLL interface, the iPort connects to a PC's RS-232 port.

The iPort can be a bus master or slave, and supports multi-master operation, arbitration detection, and clock-stretching by a slave device. The iPort supports I2C Bus mastering at 12.5 and 100 kHz, and RS-232 baud rate of 19,200. Based upon a Philips Semiconductor microcontroller, the iPort provides an industry proven implementation of I2C Bus technology, and is fully licensed to use this technology.

The iPort includes two (2) Windows applications (Message Manager and Message Center) that help a user get started sending and receiving I2C Bus messages quickly.

Custom Programming: A user developing a custom iPort Windows application will also need our iPort Software Development Kit. An application program makes calls to functions in our Windows DLL included in the kit. The kit includes our User's Guide, and application examples in C, MSVC++, and Delphi.

Recommendation: We recommend our iPort for less data intensive applications, and for application developers that need to interface with the I2C Bus via a Windows DLL.


iPort DLL/USB (Windows USB/DLL Interface)

The iPort DLL/USB (#MIIC-201D/U, Data Sheet, User's Guide) I2C Host Adapter provides a USB upgrade path for custom Windows 32-bit software developed for our original RS-232 based iPort (#MIIC-201). Based on a USB physical interface, and Windows DLL programming interface, the iPort DLL/USB connects to a PC, or external USB hub, via a USB port.

Functionally compatible with our original iPort, the iPort DLL/USB can be a bus master or slave, and supports multi-master operation, arbitration detection, and clock-stretching by a slave device. The iPort DLL/USB supports I2C Bus mastering at 12.5 and 100 kHz, and includes a Virtual Communications Port driver, making it compatible with existing custom iPort software. Based upon a Philips Semiconductor microcontroller, the iPort DLL/USB provides an industry proven implementation of I2C Bus technology, and is fully licensed to use this technology.

The iPort USB includes two (2) Windows applications (Message Manager and Message Center) that help a user get started sending and receiving I2C Bus messages quickly.

Custom Programming: A user developing a custom iPort DLL/USB Windows application will also need our iPort Software Development Kit. An application program makes calls to functions in our Windows DLL included in the kit. The kit includes our User's Guide, and application examples in C, MSVC++, and Delphi.

Recommendation: We recommend our iPort DLL/USB for existing iPort (#MIIC-201) customers that have developed custom Windows 32-bit DLL-based software, but now need to port their software to a USB based physical interface. The iPort DLL/USB is recommended for less data intensive applications, and for application developers that need to interface with the I2C Bus via USB and a Windows DLL.


Variable Clock Rate (Windows DLL Interface)

The Variable Clock Rate (#MIIC-201-V, Data Sheet, User's Guide) I2C Host Adapter is a special version of our iPort Windows to I2C Bus host adapter. Capable of mastering the I2C Bus at 451 Hz to 57 KHz clock speeds, this host adapter is compatible with IC simulators and emulators that must operate the bus at low speeds. The Variable Clock Rate adapter can also be used to communicate with early versions of ICs that may not be capable of operating at full bus speeds. Based on the same Windows DLL interface as our iPort (#MIIC-201), the Variable Clock Rate adapter connects to a PC's RS-232 port.

The Variable Clock Rate adapter can be a bus master or slave, and supports multi-master operation, arbitration detection, and clock-stretching by a slave device. Based upon a Philips Semiconductor microcontroller, the Variable Clock Rate adapter provides an industry proven implementation of I2C Bus technology, and is fully licensed to use this technology.

The Variable Clock Rate adapter includes two (2) Windows applications (Message Manager and Message Center) that help a user get started sending and receiving I2C Bus messages quickly.

Custom Programming: A user developing a custom iPort Windows application will also need our iPort Software Development Kit. An application program makes calls to functions in our Windows DLL included in the kit. The kit includes our SDK User's Guide, and application examples in C, MSVC++, and Delphi.

Recommendation: We recommend our Variable Clock Rate adapter for applications requiring low I2C Bus Clock rates. These applications typically include device simulations and semiconductor devices that cannot operate at normal I2C Bus speeds..

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

I2C is just a mouse click away TM