From: nowhere@never.at   
      
   On 11/11/2023 08:57, Robert Pengelly wrote:   
   ...   
   > so that part is sorted I just don't know what interrupt get fired.   
      
   have you enabled and covered it by a routine where its address need to   
   be stored into the Interrupt Table ?   
   __   
   wolfgang   
   oh, and I forgot to mention that old hardware need delays between I/O   
   writes (2..5 mSec)   
      
   more info from RBIL about IRQ->INT and ENABLE:   
      
   port A0 work equal for IRQ 8..15   
      
     PORT 0020-003F - PIC 1 - PROGRAMMABLE INTERRUPT CONTROLLER (8259A)   
   SeeAlso: PORT 00A0h-00AFh"PIC 2",INT 08"IRQ0",INT 0F"IRQ7"   
      
   0020  -W  PIC initialization command word ICW1 (see #P0010)   
   0020  -W  PIC output control word OCW2 (see #P0015)   
   0020  -W  PIC output control word OCW3 (see #P0016)   
   0020  R-  PIC  interrupt request/in-service registers after OCW3   
   		request register:   
   		 bit 7-0 = 0  no active request for the corresponding int. line   
   			 = 1  active request for corresponding interrupt line   
   		in-service register:   
   		 bit 7-0 = 0  corresponding line not currently being serviced   
   			 = 1  corresponding int. line currently being serviced   
      
   0021  -W  PIC ICW2,ICW3,ICW4 immed after ICW1 to 0020 (see   
   #P0011,#P0012,#P0013)   
   0021  RW  PIC master interrupt mask register OCW1 (see #P0014)   
      
   Bitfields for PIC initialization command word ICW1:   
   Bit(s)	Description	(Table P0010)   
     7-5	0 (only used in 8080/8085 mode)   
     4	ICW1 is being issued   
     3	(LTIM)   
   	=0  edge triggered mode   
   	=1  level triggered mode   
     2	interrupt vector size   
   	=0 successive interrupt vectors use 8 bytes (8080/8085)   
   	=1 successive interrupt vectors use 4 bytes (80x86)   
     1	(SNGL)   
   	=0  cascade mode   
   	=1  single mode, no ICW3 needed   
     0	ICW4 needed   
   SeeAlso: #P0011,#P0012,#P0013   
      
   Bitfields for PIC initialization command word ICW2:   
   Bit(s)	Description	(Table P0011)   
     7-3	address lines A0-A3 of base vector address for PIC   
     2-0	reserved   
   SeeAlso: #P0010,#P0012,#P0013   
      
   Bitfields for PIC initialization command word ICW3:   
   Bit(s)	Description	(Table P0012)   
     7-0	=0 slave controller not attached to corresponding interrupt pin   
   	=1 slave controller attached to corresponding interrupt pin   
   SeeAlso: #P0010,#P0011,#P0013   
      
   Bitfields for PIC initialization command word ICW4:   
      
   --- SoupGate-Win32 v1.05   
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