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Lpc2000

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Message

Re: initializing I2C problem

2005-04-13 by neptunus1000

Hello Aalt,

with on both lines a pull-up the code is still not working oke. 
Please help my.

--- In lpc2000@yahoogroups.com, "Aalt Lokhorst" <lokhorst@s...> wrote:
> Hello Roy,
> 
> Is there a pull-up on the SCL line? I can't find it in the 
schematic 
> drawing but probably I missed it.
> 
> As far as I know both lines need a pull-up because SDA and SCL 
lines are 
> 'open-drain' outputs.
> 
> Best Regards,
> Aalt
> 
> -- 
> ==============================
> Aalt Lokhorst
> Schut Geometrische Meettechniek bv
> Duinkerkenstraat 21
> 9723 BN Groningen
> P.O. Box 5225
> 9700 GE Groningen
> The Netherlands
> Tel: +31-50-5877877
> Fax: +31-50-5877899
> E-mail: Lokhorst@S...
> ==============================
> 
> neptunus1000 wrote:
> > 
> > Hello,
> > 
> > I use an olimex evaboard (LPC2129) and crossStudio.
> > I would like to use the I2C interface but it won't work.
> > ARM should be the master. First I tried to code it on my own with 
the
> > datasheet. Then I found some example code on the group.
> > 
> > The methode InitI2C() is working fine. Only the methode
> > SendSlaveAdress(unsigned char Addr_S) is working not well. 
At "while
> > (I2STAT != 0x08); // Wait for start to be completed" my code stops
> > and is waiting for de SI bit to set. This is never happening. I 
don't
> > understand why it is already stopping here.
> > 
> > I have nothing connected to the I2C bus, I mean that there is only
> > the EEPROM. Which is standard on the evaboard. I'm using 0xA0 
address
> > for writing and 0xA1 for reading. But it can only by a matter if 
the
> > code can past this line of code "while(I2STAT != 0x08);"
> > 
> > For who have an interest this is the link the de pcb plan.
> >  
> > http://microcontrollershop.com/Images/lpc-e2124-sch.gif?
> > osCsid=3e8281154ae1883323bdf695bf87d276

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