Ring buffer or queue for different datatype

Question

Hi, 
 I want to sample ADC signals and send data when requested via BLE or UART. I set a timer that triggers every 100 ms and gets ADC data. To store the data, I would like to use some large buffer that will store incoming data. If the buffer reaches end limit and previous data isn't pulled out, it should overwrite the first data and while reading it should start reading from first data (of course not overwritten one) simple: FIFO with first in data replaceable if size full. I think Ring buffer should solve my issue but the problem is with its data type. The datatype of ADC values is uint16_t while ring buffer has uint8_t so I have to break values in two 8 bytes and store them. 
 Ring Buffer 
 Queue library 
 I read a post about the difference between ring and queue here but it is a general discussion and states both are the same. Could you please suggest what mechanism shall I use and do I need to modify nrf ring buffer library to support the required data type?

haakonsh · Accepted Answer

Ali Rumane said: The nrf_ringbuf_cpy_put API accepts data as uint8_t, so I can't put any other datatype like uint16_t or something so how will it work for my application? 
 You store an array of data no matter what type it is. Whether you access the data as uint8 or int16 won't change the data itself. I suggest you read up on Type Casting and Pointer Type Casting in C as it is fundamental in understanding your problem and its solution. see f.ex. https://stackoverflow.com/questions/17260527/what-are-the-rules-for-casting-pointers-in-c/17260931 
 Ali Rumane said: Let's say I want to store 5 bytes data so do I deliberately need to store 0 or some other value so that data becomes 6 which is multiple of 2 and ignore while retrieving it? 
 Int16's are exactly two bytes of data. If you want to store 5 uint8's then you will need 5x1 bytes, but if you want to store 5 int16's as uint8's it will require 5x2 bytes.

Ring buffer or queue for different datatype

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