For the purpose of explanation, lets assume the following:
-We have a simple function: f(takes in 8 bits)= outputs 4 bits, or any similar simple function.(ex. f(a,b)= (a x a + b x b + 11) mod 15, where a,b are 4-bits)
-We have a 2 block message: M=101011110.
-The initial IV = 1111 or a similar simple IV
To my understanding, the first 8-bit block is 'a=1010 b=1111' and it would go through the function f(). I am unsure of how the IV would fit in to the process at this point, and how the IV would take action for the second block and so on. Any help is appreciated, and perhaps it may be the case that generalized variables as opposed to my specific numbers would make this example easier to explain in an answer.