I want to know what is the difference between the internal data DRTY ready and the external. Which one should I use? It is much easier to use the internal data ready so why would I use the external?
The option is up to you. The DRDY pin is level sensitive and could be used as an interrupt for a microcontroller, for example to indicate that the data is ready and has been read.
The other option is for you to keep sending the header (Bit 6 in the frame control register) until the data is ready until data is ready.
Thanks for your email.
There's no difference between the internal and external DRDYb signal - they both reflect the same information in the same timeline (if low, data is ready).
Using the internal DRDYb status bit from the Header word is very useful if you don't want to dedicate an SPI line for the hardware DRDYb signal. This will require your micro to analyse the status bit and act accordingly (wait and keep reading the header if not ready).
Hope this helps!
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