From: muta...@gmail.com   
      
   On Wednesday, June 16, 2021 at 8:19:19 PM UTC+10, Joe Monk wrote:   
   > Remember, COM ports are tied to IRQs. IRQ3/4.   
   >   
   > There are only 4 because thats all the 8250 UART could provide, and the 8259   
   PIC could only give up two IRQs.   
   >   
   > If you use a driver, such as a digiboard, then it could handle more via   
   software interrupt...   
      
   The BIOS manufacturer can provide as many devices   
   behind that interrupt as they want.   
      
   The normal INT 14H is polled anyway, for read.   
   Not sure if something depends on an interrupt   
   for the write. But the manufacturer can share an   
   interrupt or anything else they want to do.   
      
   BFN. Paul.   
      
   --- SoupGate-Win32 v1.05   
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