Specifications

Application Examples
Initialize the 8840 Interrupt Controller
Send ICW1 - Edge triggered, Cascade, ICW4 needed
Send ICW2 - Vector addresses 248 - 255 D
Send ICW3 - Slave interrupt controller ID #2
Send ICW4 - SFNM, Buffered Slave, Normal EOI, 8088
Send OCW1 - Unmask interrupt IR0
END
INIT_VECT Routine
BEGIN
Initialize low memory with a pointer to the interrupt
service routine (ISR)
Write offset of ISR to lower word
Write code segment to next higher word
(This sequence would repeat for more than one ISR)
END
INIT_UART Routine
BEGIN
Initialize the 8250 on the ZT 8840 for the following:
8-bit data
9600 baud
No parity
No interrupts enabled
END
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