Hi Fabiola,
I'm sorry for my delayed response.
- I agree that the order of operations is sketchy. A WAKEUP command is the proper way to exit standby mode, but it is possible to interrupt standby mode with SCLK activity while the /CS pin is low.
- I don't like either! It sounds like /DRDY is performing an update pulse (refer to Figure 4 on page 7 of the data sheet). If a data read operation has not completed, /DRDY will stay low until the next conversion completes and data is getting written to the output buffer. It is possilbe that data read is able to sqeak out the last bits of data before the output buffer is updated, but then again, you don't know if the last bits comming out correspond to the lastest conversion result.
You definietely want to see the read operation complete before this happens. It is odd for this to be an issue when the /DRDY pin is being monitored, unless the processor is reacting slowly to the /DRDY falling edge or if the SCLK speed is slow and data read back is taking too long. If a fast sampling rate is causing too tight of a timing requirement, then you may need to recommend using the data "read by command" method, which will not produce corrupted data when conversion results update during the read operation.
Best Regards,
Chris