Code review for microcontroller 8051

I'm working with microcontroller 8051. I'm trying to simulate serial comunication on RS232 port. To do that, I need to take a single bit by bit from a number (ASCII value of a char) and put it on the port for certain amount of time.

Here is a part of my code, which might be problematic.

BITS set 60h
MOV BITS, #8            
index set 0             
sendDataBit:
JB 20h.index,set1       
CLR T                   
return:
CALL waitDataBit        
index set index+1
DJNZ BITS,sendDataBit 


set1:
SETB T              
AJMP return 

I stored my ASCII number in address 20h (bit-addressable area). Now I want to access every bit of the number separately. Idealy in a loop with dynamic indexing.

The only way it work for me is to define variable index and re-define it in each loop to incremented value. But 'set' is not a instruction of the microcontroller. I'm sorry, I don't know the terminology here. And I need to precisely time whole process. With 'set' I don't know what's happening in there.

So that's why I don't like this part of my code. What do you dislike about it? Could anybody explain what is happening when running this code? What is the better solution for my problem?