Phillips 68070 I2C software - information sought

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Hello

I am maintaining the software of a 68070 based board which uses the
processors internal I2C controller to communicate to up to 16 slave
processors.
This I2C bus locks up under specific conditions.

The 68070 built in I2C controller is configured as the I2C master polling
the 16 slaves for data.

The problem I have is that the 68070 data book is *very* skimpy with regard
to the I2C controller register definitions.

Have googled for information but as this part is obsolete I have come up
against a brick wall.

Has anybody written low level software for this part or has data sheets /
applications notes for it that may have since dissapeared from the phillips
site.
I have the general I2C specification etc. but need specifics for the 68070.

Thanks in advance

--
Robert Manktelow @ Work



Re: Phillips 68070 I2C software - information sought
I have downloaded and archived datasheet and maybe app notes for 68070. What
do you want specific?
Regards -
Henry

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Re: Phillips 68070 I2C software - information sought
Hello Henry
Thanks for the reply.

I am desperately searching for any information, beyound the 68070 User
Manual which I already have regarding the I2C controller in the 68070. I.e.
its registers bit definitions - what is set by controller automatically/what
can be set by processor + Any application notes or code that uses this part.

I am searching for confirmation/denial of the assumptions I have made from
the limited information I have here.

Robert

--
Robert Manktelow @ Work
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Re: Phillips 68070 I2C software - information sought
Hi Robert -
Hm. Try the documentation on the PCFxxxx i2c bus controller from Philips.
Surely the 68070 use the same or similar logic.
- Henry

Robert Manktelow schrieb in Nachricht ...
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automatically/what
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part.
polling
/
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Re: Phillips 68070 I2C software - information sought

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This may or may not be an i2c master problem.
Slaves are allowed to stretch the bus to reduce clock speed temporarily.
Therefore a slave may cause a bus lock and the master - if implemented
without timeout - waits for ever and a day for the bus to be free again.
Are you using an i2c tracer like
http://www.tracii.de
to check whether the lock occurs during a certain slave operation or
arbitrarily?

The other way around is also a common cause for problems.
Some masters simply do not recognize bus stretching and this works perfectly
as long as no slave ever uses this feature. However as soon as stretching
occurs the state machines get messed up which is also likely to result in a
bus lock.

/Roland



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