x = 16'0xBEEF
y = 200'0x0
z = 16'0xCAFE
zero_extend(z) = 32'0xCAFE
q = 72'0xABFEEDDEADBEEFCAFE
k = 8'0xFF
k + k = 8'0xFE
0xFF + 1 = 8'0x0
0xFF + 2 = 8'0x1
0xFF + 3 = 8'0x2