Lpc2000

Hello,

"Was there indeed a pull-up resistor missing on the Olimex board?" 
YES there was one missing.

I put for the testing two pull-up on the bus of 4,7K and connected to 
the 3.3 Volt. When I'm debugging the program. The program is still 
hanging on the while(I2STAT != 0x08);. When I measure the both I2C 
lines with pull-up, the lines have 3.3 Volt. The program is not 
working. If I disconnect the pull-up resistor the SDA line is 3.3 
Volt and the SCL line is 0 Volt. This is oke if I look in the schema 
of the Olimex board. I really don't understand why it is not working.

Of course I can build some code for 'bit-bang', but if the uC has a 
I2C bus. Then it is ugly to build a 'bit-bang' routine.

I measured with a FLUKE 123 scope meter.

Best Regards
Roy

--- In lpc2000@yahoogroups.com, "Aalt Lokhorst" <lokhorst@s...> wrote:
> Hello Roy,
> 
> Was there indeed a pull-up resistor missing on the Olimex board?
> 
> If you can measure low and high levels on both I2C lines now then I 
> expect that the hardware is fine. If there is also a I2C device on 
the 
> bus and it is still not working then i assume it is a software 
problem.
> 
> In the past I used I2C on a 8051 with some 'bit-bang' routines. 
Until 
> now I didn't use the I2C of the ARM. This will change in the next 
few 
> weeks but for the moment I can't help you.
> 
> In the files section of the yahoo group are some examples. If the 
> pull-up indeed was missing in the hardware then you probably spend 
a lot 
>   of time with software debugging without any change to succeed.
> Might be the moment to start debugging again, use an oscilloscope 
if you 
> have it and study the signals to see where it fails.
> 
> 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 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...
> >  > ==============================