🚀 go-pugleaf

Hello,  

     I need a little help with a question some one gave me. I am doing
the question to see if I can. The question is as follows :-

Write a short program in 8086 assembler that can receive serial bytes
from COM1 and immediately re-transmit the same bytes through  COM2
The baud rate should be user configureable and the bytes passing
through should be displayed on screen as hex and or characters,
either both at once or user selectable. No extra functions are required
but extra functions and presentation quality will be an advantage.

I have programmed in C for IBM PCs but never 8086. Taking a simples view
I expect is will be a case of having an address for COM1 , setting
the reqisters for the required function, ie baud rate , TX , RX and
when a receive is given , taking the data and out putting it to com 2
which also has been set up.

When I programmed in C there was a number of interupts available
to do all sorts, I no longer have the MS-DOS Bible. There was one
in particular that allowed the cursor to be moved around the screen
by setting the reqisters and calling the interupt.

Can anyone give me any information regarding how to call the interupts
using assembler and what interupts will I need for the task ?

Is there a way of calling the system at run time to give details 
of the comms ports ?

Does anyone have any code that could be of use to me ?

How do I set up my own interupt service routine so that once the 
program polls the coms port for data it can jump to code that allows the 
system setup to be changed ie change baud rate ?????


Answers to Me via Email please on jsk@uniplex.co.uk and I will be
able to have a merry christmas without spending my time thinking 
about it. 

I expect I will have to read a few books on the subject but at the moment
I have no way of getting any. I also know that the information I need to
complete the task will  probably be at an FTP site, pity I can't FTP !



Many Thanks

Jon King

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