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We would like read two channels: Ain0-Ain1 and Ain2-Ain3, Continous Conversion, RDYFN = 1. Figure 10 (AD7738 datasheet Rev.0) shows this example, but it is not described in the datasheet how to set it up. Can you confirm the sequence for Figure 10? Also, can you confirm if Figure 12 is correct?
(i) Regarding Figure 10, the value to be written to the channel setup registers should be 0x68 or 0x6C. Additionally, you need to set the RDYFN bit in the IO Port Register by writing 0x38 to it. (ii) Figure 12 provides continuous convert and continuous read and the datasheet is incorrect and it should be setup as follows: 1. Write 0x38 (write to comms reg to setup write to mode reg) 2. Write 0x2C (write to mode reg to set continous conversion, dump mode and cont rd.) 3. Write 0x48 (write to comms reg to setup read from data reg) 4. Read Data It should also be possible to set the RDYFN bit when operating in continuous read mode such that the RDY pin will go low only once all enabled channels have new conversion results available.