I have serial data that needs to be read, example 9 and D if I use a byte value it locks up so I never get to the D. I must echo each character to get the next so I cannot get both which is what I need 9D is what I need to come out with. I prototyped with a stamp it would catch the first character but was not fast enough for the second some of the times. I used a var byte and seriin for highnib and lownib of that byte. I tried 4 bit var it did not get it correct

any ideas