MinIMU-9 accelerometer horizontal readings

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I figured out what is wrong, here is a C# program that describes the problem:

using System;
using System.Threading;

namespace ConsoleApplication1
{
    class Program
    {
        static void your_math()
        {
            byte high = 0xC1;
            byte low = 0x80;

            var data = (Int16)(((high << 8) | low) >> 4);

            System.Console.WriteLine("your result: " + (double)data);
        }

        static void correct_math()
        {
            byte high = 0xC1;
            byte low = 0x80;

            var data = (Int16)((high << 8) | low) >> 4;

            System.Console.WriteLine("correct result: " + (double)data);
        }

        static void Main(string[] args)
        {
            your_math();
            correct_math();
            while (true) ;
        }
    }
}

The problem is that by shifting to the right before turning your number from an unsigned number to a signed one, you are basically putting a bunch of 0’s on the left side of the number, which messes up the 2’s complement form. By the way, I made this program by following my suggestion to you of simplifying your program by inserting literal values for the bytes you expect to receive.

- Ryan