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From: "Hans J. Koch" <hjk-hfZtesqFncYOwBW4kG4KsQ@public.gmane.org>
To: i2c-GZX6beZjE8VD60Wz+7aTrA@public.gmane.org
Subject: Two start conditions for PCA9554
Date: Tue, 29 Apr 2008 15:11:14 +0200	[thread overview]
Message-ID: <20080429131114.GF3195@local> (raw)

I have an embedded board with a PCA9554 on it. It's an 8-bit IO expander
similar to the PCF8574 in mainline. One difference is that when reading
from the inputs, you have to do the following:

- start condition
- send slave address, R/W=0
- send command (0x00 = read input register)
- issue another start condition (!)
- send slave address, R/W=1
- read data
- stop condition

Can such a protocol be handled by the i2c subsystem?

Thanks,
Hans


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             reply	other threads:[~2008-04-29 13:11 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-04-29 13:11 Hans J. Koch [this message]
2008-04-30 21:26 ` Two start conditions for PCA9554 Trent Piepho
     [not found]   ` <Pine.LNX.4.58.0804301422140.9894-13q4cmjDBaTP3RPoUHIrnuTW4wlIGRCZ@public.gmane.org>
2008-05-01 20:39     ` Hans J. Koch
  -- strict thread matches above, loose matches on Subject: below --
2008-05-01  6:01 David Brownell
     [not found] ` <200804302301.56732.david-b-yBeKhBN/0LDR7s880joybQ@public.gmane.org>
2008-05-01 20:35   ` Hans J. Koch

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