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can't pull down twi data line as slave http://www.at91.com/samphpbb/viewtopic.php?f=15&t=1969	Page 1 of 1

Author:	ak187 [ Wed Jul 05, 2006 4:52 pm ]
Post subject:	can't pull down twi data line as slave
Hi, I'm trying to implement a software TWI slave on at91sam7s256, but i got a problem on pulling down the data line for acknowledge. As far as i understood the specification, the clock/data-line should be open-collector. My TWI master is configured as open-collector but when i try to clear the output the data line still remains high, so that the master doesn't see the slave. I tried to change the IO port to output and clear the IO port and set it back to input after acknowledge. This works, but is very time critical since a have a 100 khz clock to serve. Another question is: Reading the GPIOs takes a very long time. Is there a mistake in my source or is it the AT91SAM, which needs so much time? thanks Anibal

Author:	seulater [ Tue Jul 11, 2006 5:53 pm ]
Post subject:
GPIO ports are faster than on other ARM7s -Olimex

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