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Reading data from i2c and storing results in PIC

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Newbie level 6
Jul 19, 2002
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i2c com pic16f84a

I wish to intercept the I2c informations between a microcontroler and a 24lc32, store these infos in the internal 16f84 eeprom to use same (after eventual modifications) on an other ic2 bus.
In fact, the initial system is a microcontroler (which cannot be modified) acting as master of a chain, when an order is given either by button ot IR remote, the necessary infos (channel specifications) are asked to a 24lc32 which after treatments in the controler are used to command various items on the same i2c bus(tuner, LCD etc)
I connected a pic 16f84 on this bus but unfortunately it is impossible to read (and of course store) the 8 octets of the EEprom corresponding to the choising channel.
In any case as the pic is not configured to be a slave or a master no any "STAR","ACK" or "STOP" are sending and cannot be send as i wish only to pick up the infos in parallel.
I used "SHIFTIN" (PicBasicPro) without result.I obtain some infos without any relation with the EEprom Data.
Can any body help me??

Thanks in advance

i2c reading in pic

Step by Step,

You want to spy an I2C bus made betwen a uC and a E2Prom don't you?.

If this is correct you only have to monitoring SDA line, and SCL . So place two buffers betwen bus and you uC. And make a Pulling of SCL line. as soon as it make a change test SDA line, so you can know if there is START condition STOP ACK etc.

i'll hope be useful

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