Application Examples
SERIAL_8250 Routine
BEGIN
Indicate to the main program that the interrupt was
received
Disable further serial interrupts
(no more are desired in this program)
Send EOI to the ZT 8809A
Send EOI to the ZT 8840 Interrupt Controller
Return from Interrupt
END
MAIN Program
BEGIN
Initialize the segment registers and stack
Use the routine to initialize the vector(s)
Call INIT_UART
Call INIT_PIC_8809A
Call INIT_PIC-8840
Enable the interrupt inside the UART for transmit
buffer empty
Enable processor interrupts (STD DOS already has
them enabled)
Send a byte, which should be shifted out and prompt
an interrupt from the UART
Wait for the byte to be sent, then check to see that
the interrupt was seen, indicating that the transmit
buffer is ready for another byte
Strobe the LED if the interrupt was seen
END
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