why is the result of this simple code about Appdecoder wrong?

i use system object block to encode and decode a data stream as u see in the written code below. but i dont know when i compare the data with the decoded data, its result is completely wrong, can anyone know its reason?

    % clc;    
clear all;    
Data1=randi([0 1],300,1);    
H=comm.ConvolutionalEncoder('TrellisStructure',poly2trellis(5,[23 35]),'TerminationMethod','Truncated');    
h=comm.APPDecoder('TrellisStructure',poly2trellis(5,[23 35]),'TerminationMethod','Truncated','Algorithm','True APP');    
y=step(H, Data1);    
x=step(h,zeros(300,1),y);    
b=double(x >0);    
v=Data1-b }