Calibre UK PICA93LV Most Commonly Asked I2C Questions, Try again I cant get anything whats wrong?

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CALIBRE

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THE MOST COMMONLY ASKED I2C QUESTIONS

6.1.General Questions

Question

Will my adapter run I2C clock speeds greater than 90KHz?

Answer

At the moment your adapter is limited by the Bus Controller chip fitted, to a maximum

 

of 90KHz as a master and 100KHz as a slave.

Question

Will my adapter work under Windows NT4* or Windows 95*?

Answer

The adapter will work under both these systems without problems. If you need to

 

access the Windows NT and Windows 95 DLLs please contact our sales team for

 

further information.

 

* All trade marks acknowledged

Question

I get corrupted transfers why is this?

Answer

The most likely reason for corrupted transfers is either incorrect bus termination or

 

excessive capacitance - see the manual for details.

Question

Do you have software to talk to my........?

Answer

Unfortunately there are too many I2C devices for us to be able to offer complete

 

solutions - although we can supply a windows based application called WINI2C which

 

is designed for those just starting I2C or wishing to perform simple I2C tasks, please

 

contact our sales team or look on our web site, www.calibreuk.com for further

 

information.

Question

I am trying to read from a device, the first time my software works fine but when

 

I try again I can't get anything what's wrong?

Answer

Please check that you are changing the value of Setnack in accordance with the

 

manual, it is likely that you have not made Setnack 1 for the last AND last but one

 

bytes being read.

6.2.DOS Software Questions

Question

My I2C adapter locks up with a constant status - why?

Answer

If you are using either the 'C' or Basic library functions supplied with the adapter on a

 

fast PC it is possible that the PC is polling the status register too quickly, the simplest

 

way to prevent this is to add a small delay prior to reading the status in the getstatus

 

routine. Alternatively use the windows DLL supplied as these automatically allow for

 

speed of the PC at run-time.

6.3.WINDOWS 95 and NT Questions

Question

My software cannot find the adapter. Your Windows software reports that it

 

cannot configure the adapter. Why is this?

Answer

Have you registered the device driver as detailed in the software manual? If so check

 

that the address links (see adapter manual for details) are correct for the location at

 

which you registered the driver.

Question

I think I have registered the driver how can I find out if I have?

Answer

You need to inspect the registry as follows

Issue 1.3

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Contents Calibre Copyright CalibreContents Introduction Configuring the AdapterGeneral Introduction Packing ListTypical PC Connection Installing the AdapterConnector Pinout Connecting the Adapter to Your SystemPower Supply Bus Capacitance Limitations\C\CLIB\SPICA.LIB Software Utilities\C\CLIB\CPICA.LIB \C\CLIB\MPICA.LIB\B\SOURCE\I2CINC.BAS DOS Qbasic Library/Programs\B\SOURCE\PROMREAD.BAS \B\SOURCE\PROMWRIT.BASWindows LIB/DLL Functions Routines Using the UtilitiesInt ownaddress Int sclkInt i2cstatus Int slaveaddressInt setnack Calibre Int i2cdata Calibre Int i2cstatus Number if the adapter is to read from the slave Ownaddress% Qbasic RoutinesSclk% I2cstatus%Slaveaddress% I2cdata% Setnack%See Appendix a for details status codes I2cstatus% Is to read from the slave Libraries for Programming in Microsoft Windows Environments Int baseaddressInt statuswait Int wrData Int ErrCodeSendaddress Address to be accessed via the I2C, e.g. A1H Int sendbytesint far *transferarray Int far *transferarrayInt bsent Int nobytesread Int getbytesint far *transferarraySlave using the adapter Further Information Appendix a Parallel I2C Communications Adapter Status Codes Bit 4 The Bus Error BER BitBit 7 MSB The Pending Interrupt Not PIN Bit Bit 6 Not UsedAppendix B Parallel I2C Communications Adapter Control Codes Most Commonly Asked I2C Questions Question Get corrupted transfers why is this?Question Do you have software to talk to my........? QuestionCode. Why? Please Email Your Query to