The Influence after change the PC language to vb 6.0

i have using vb6.0 to develop the LIS system that link to analyzer with serial port.

That is no problem happen when my pc language setting 'Language for non-unicode program' = English(US). Because the 1st char STX sending by analyzer is chr(2) ='' and last char is ETX is chr(3) =''. So i can using the coding to check whether the result have complete send or not by checking the 1st chr(2) and last chr(3)

example : if instr(1, strData,chr(2) then
if instr(1, strData,chr(3) then

sometime send in batch then i have to seperate the result using this 2 char too.

The Problem now is when i change the pc language setting 'Language for non-unicode program' = Chienese (PRC). all the unicode become □.
chr(2)= □, chr(3)= □, chr(4)= □

so when the pc have receive the result from analyzer it cannot capture the chr(2) will ingone the work. so no result will display after sending the result.

The perpose i change the pc language setting 'Language for non-unicode program' = Chienese (PRC) is because i need to display the chiense word on vb6.0 interface and crystal report.

How to solve this problem that can make the vb6.0 and crystal report display and print out the chiense word, and the unicode remain the orignal char?