24 Feb
2006
24 Feb
'06
3:56 p.m.
Though there's a nifty adapter board to plug it
into an Apple 2's joystick
port.
I am suprised you have enough signals on the Apple ][ games port, but
maybe you do...
I don't think the interface itself actually had
any LEDs, and there's a
The BBC one certainly does.
diagram showing pinout for the motor control lines on
the top of the case.
There's also several lines that you can attatch switches to, we've gota
paddle with paperclips on it :)
This interface was designed to work with the origianal Fischertechnik
robotics kit. This kit contained 2 minimotors (small DC permanent magnet
motors), an electromagnet, 3 lamps, 8 pushbutton switches, and 2 pots,
along with the standard mechanical parts.
It was conentional to wire a lamp in parallel with any motor or
electromagnet you were using in the model. Or you could use the lamps
separately (the first model was just a set of traffic lights using the 3
lamps). You could use the swtiches either as user input buttons or as
limit switches, etc for parts of the model.
5
fischertechnik sockets. One is logic ground (marked with an upside-down
T). The otehr 2 are 2 pairs for power supply inputs. They were designed
to link to a fishcertechnik transformer, you need a DC supply of 7-10V.
It's used directly to power the motors, rgulated down to 5V for the
logic. You only need to use one set (particularly if you have a nice
bench supply...), and there are internal protection diodes if you connect
the supply backwards.
So I won't blow it if I make a mistake? We've got all that, I'm looking more for
programming guidelines, as we've
got next to nothing in documentation (Perhaps one apple 2 doc for
interfacing with it, and I'd like to use my portfolio to control it,
somehow.)
I suspect this is differnt, but not very, on the BBC version.
It is not hard to trace out the schematics (give a 4000-series databook
:-)). That would tell you what the signals from the computer do.
The driver, at least for the C64 and BBC version, was a machine code
program. I think you got a binary program for the C64 that you called
with SYS. The BBC version was written in assembler (the BBC BASIC
interpreter includes an assembler). It's not commented, but it's fairly
easy to follow (even for a non-programmer like me). Of course it makes
use of the 6522 VIA chip in the Beeb (and it talks to it correctly, via
an OSBYTE call, so you can run it on the 65C02 second processor).
I've got several tons of GWBASIC files from a four floppy disk set, and I'm
going to tear those apart soon.
I wonder if any of those are equivalent to the ones on the BBC disk.
Comparing them might be interesting...
-tony