Ada interrupts

[newsflash.concordia.ca!nstn.ns.ca!jmacleod@uunet.uu.net (James Mac Leod)]

I am looking for information on how to write interrupts in 
Meridian Ada 4.1.4 for serial communications on a 286 PC.  I am familiar 
with the 8250 UART chip in the 286 and how to initialize it (i.e. the baud 
rate, parity, etc).  The problem is how the Ada tasks work.  I have tried 
using entry clauses to both interrupt C and B  but neither appear to work.  
I have also tried saving the DOS interrupt vector using DOS function call 
250C and restoring using 350C.  Are these functions only for interrupt C?  
If so what are the function calls for interrupt B?  A similar program 
written in Alsys Ada works on an XT which uses interrupt C.  The 286 has a 
different serial port address so maybe it should use interrupt B.  The port 
is at address 2F8H.  Any body give me a hand?  It would be greatly 
appreciated.

Jamie

My EMAIL address is: jmacleod@fox.nstn.ns.ca
		
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