SUPER MICRO Computer MIIC-203 manual Connecting to a 3.3v System, Connecting to an SMBus System

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Hardware Configuration

Pull-up Resistors

The iPort/AFM Host Adapter includes a slide switch used to enable or disable internal 1.8K ohm Pull-Up resistors on the SCL, SDA, and INT lines. Every I2C Bus system must have at least one Pull-Up on each line. Use this switch to configure the iPort/AFM appropriately for your system.

Connecting to a 3.3v System

1.Shut off iPort internal pull-ups. (See Pull-up Resistor section)

2.Use external pull-ups to 3.3 volts.

The iPort uses a 5 volt device. 3.3v is high enough for the iPort to see a Logical 1.

Connecting to an SMBus System

1.Shut off iPort internal pull-ups. (See Pull-up Resistor section)

2.Use external SMBus rated (approx. 15k ohm) pull-up resistors.

Hardware Set-Up

1.Attach your iPort/AFM (#MIIC-203) to an open ComPort on your computer. If your ComPort has a DB9 connector, use DB-9F to DB-25M Serial Port Adapter Cable included with your iPort/AFM to connect.

2.Connect the power supply provided or see Interconnect Section +5VDC Power Jack.

3.Connect I2C Interface Cable to iPort/AFM and your I2C device. If your device does not have the matching connector (#15830064) you can cut the end of the cable and attach the individual wires to your device or you can purchase our clip-lead cable(#CABCL).

4.Connect INT line if used.

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Contents 479,12 Introduction Page Table of Contents Programmer’s Reference Ascii Command Interface Definitions Page Part Model MIIC-203RS-232 to I2C Host Adapter Ascii Fast Mode Interface OverviewRS-232 Serial Port Connector System RequirementsInterconnects Packing Slip+5VDC Power Jack DB-25 Serial Port PinoutI2C Interface Connector INT, Interrupt Signal ControlConnecting to a 3.3v System Connecting to an SMBus SystemHardware Set-Up Pull-up ResistorsIPort Utility Pack for Windows IPort Message Center Introduction to Utility PackIPort Message Manager Software Installation Page I2C Message Operations Page Page Page Starting the program Select iPort DeviceEstablish iPort Link Basic Set-up Advanced Set-up Diagnostic Set-up iPort Only Sending Messages Master Operations To Master Transmit DataTo Master Receive Data Uninstalling iPort Utility Pack To Slave Transmit a messageTo Slave Receive a message Programmer’s Reference IPort/AFM Quick Start IPort/AFM Ascii Text Interface Commands Command DescriptionIPort/AFM Reset Synchronous Interface EventsStatus Display RS-232 Baud RateClose I2C Connection Set Destination I2C Slave AddressEcho/Prompt Control Flow ControlI2C General Call Control Hex Only Display ControlCommand Menu Display Set iPort/AFM’s Own I2C Slave AddressI2C Bus Clock Rate Control Interrupt Signal Control/Status Open I2C ConnectionMaster Read Message Slave Transmit Message Master Transmit Message EXtended Commands requires V2.00+ Set I2C Bus Time-oUt in msecDisplay Firmware Version requires V2.00+ Page Issue a Read WCR command to a Xicor X9241 at slave address Display Tx bYte Count requires V2.00+ Asynchronous Interface Events Slave Transmit RequestSlave Receive Complete General Call Receive CompleteINterrupt Signal Assert INterrupt Signal ReleaseI2C Bus Time-out Detected I2C Bus Error Detected IPort/AFM PromptsIPort/AFM Ready Slave Not AcknowledgingInvalid Command Argument Invalid iPort/AFM CommandIPort/AFM Connection Closed Slave Transmit Request Not ActiveExample Code IPort/AFM InitializationMaster Receive Message Communication Event ProcessingPage Page Page IPort/AFM Revision Report RevisionAdditional Information Micro Computer Control CorporationLimited Warranty Life Support ApplicationsLimitation of Remedies and Damages Appendix a