In our system we are using the PGA309 frontend and we control it trough a microcontroler with the One-wire Interface.After we write the complete EEPROM, we read the ZeroDAC register and we get a wrong answer from the PGA309. It returns 0x5449 ("TI") instead of the DAC value.After 1 second of communication silence we read the correct value. Is this normal way to do it?
Programming on OMAP L138, LogicPD evm board
While 0x5449 is the TI Flag value in the external EEPROM, 0x5449 is also a valid setting for the Zero DAC register. Is this always the value read during this sequence or is there any variance?
In normal operation, the PGA309 reads back from the EEPROM roughly once per second. How soon are you reading back the register after performing an EEPROM write? It's possible that not enough time has passed for the PGA309 to initiate an EEPROM read and update its registers. Once you allow the second to pass, it has been properly updated.
Ian WilliamsLinear Applications EngineerPrecision Analog and Sensing Products
Thanks for your reaction. Here are some answers on your questions.
Is this always the value read during this sequence or is there any variance?
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