System Interrupts - IBM 5170 Technical Reference

+5 Vdc
-Rafrash
o
Rafrash Raquast
0
Clock
'----
Claar
System Bus
--..
­
Gate 0
-
Clock In 0
+5 Vdc
Gate 1
t--- Clock In 1
110 Addra ss
Hax 0061
Gate 2
Port Bit 0
t--- Clock In 2
To 8259A IRO 0
Clock Out 0
Clock Out 1 >­
Driver
I
110 Address
Clock Out 2
AND
I
Low
Pass
~ To Spaakar
Hax 0061
Port Bit 1
PCLK
Divide
D
Flltar
(2.38 MHz) by 2
System Interrupts
The 80286 Microprocessor NMI and two 8259A Interrupt
Controller chips provide 16 levels of system interrupts. The
following shows the interrupt-level assignments in decreasing
priority.
Note: Any or all interrupts may be masked (including the
microprocessor's NMI).
1-10
System Board