How to read previously written data

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originally posted by kofinator@Mar 20 2007, 12:26 PM

hello,

i'm using the de2 board. i want to write and read from a one bit port. i built my hardware in quartus and did the software programming using nios ii ide. using a biredictional port enables me to write and read but not read the previously written data.

i would like to know how to read my previously written data from the same one bit port.

thanks.

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I guess you are using the PIO component in bidirectional mode? Usually a port itself does not hold signals. Therefore, if there is no other components connecting to the port to store the data you wrote, the data will get lost when the write operation is ended. So when you read it later, you cannot get the previously written data.

Or if you already have something connected there, could you post a little more details about your system ? Thanks.