<> Yes. The 8259 PIC (interrupt controller) is fully programmable for edge
<> and level. It's possibel to go from edge to level on a common PC but you
<
<
<Unfortunately the interrupt inputs on the 8259 are always active high
<(specified clearly in the data sheet), so you still need inverters on all
<the inputs for active-low lines.
Yes and they would be needed as putting raw unbuffered mos inputs on a
bus is bad form.
<all, the reason for having a PC is compatibility. There are plenty of
<nicer machines to hack about with (which is where we started).
yes, multibus and other implmentations were better. Even S100 got that
part right!
Allison
Received on Wed Dec 30 1998 - 21:55:35 GMT