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Re: Unknown Apple II board: "FLY BD"

Ron Kneusel wrote:

Michael J. Mahon wrote:


I've always had a fondness for 6522-based cards (like the Mockingboard)
since they have two counter/timers and two bi-directional parallel
ports (plus handshake lines), and can generate interrupts.

It's a very versatile card, and you can terminate the data cables (D1
and D2) in any way that is useful for your purposes.

Most 6522-based cards did not contain EPROMs (unless they were intended
to interface with printers), but software is usually written for each
specific purpose to which they are applied.

A little tracing of address wires will usually confirm that the chip's
16 registers are mapped directly into the /DEVSEL space ($C0sx).



I believe you are correct as to the board's purpose.  But, why are
there two cables, each with 16 wires?  There is also an EPROM (or, what
I naively call an EPROM: has a little window on it presumably to erase
it?)


Each data port has 8 data lines and two handshake lines, and it was
not unusual to run several grounds (like on a Centronics cable).


Can't seem to find anything about it online but it might be fun to play
around with if it works.  I have no idea where I got it or when.


You could easily make an LED display panel, or scan a matrix keyboard,
or drive an EPROM programmer, or control steppers, or implement a
clock in software, or drive a D/A & A/D, or...  ;-)

-michael

Music synthesis for 8-bit Apple II's!
Home page:  http://members.aol.com/MJMahon/

"The wastebasket is our most important design
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