[comp.sys.atari.8bit] Controlling a robot with an 800...

jhs@MITRE-BEDFORD.ARPA.UUCP (01/26/87)

I would suggest that you consider using the joystick ports to output commands
to the robot as an alternative.  I think on an 800 $D301 controls the 3rd and
4th joystick outputs, which have 4 bits of output each.

On the 850 interface, you are talking over the serial bus, so it is not just
a question of POKEing into an address.  I think you can send commands by
pretending it is the P: device (parallel printer) that you are talking to.
However, you may have some trouble with its wanting to buffer up a whole line
of data at a time.  You may have to be careful how you OPEN the channel to
the P: device.  You should read up on the XIO command and read the 850 user
manual carefully.

Using the joystick ports 3 and 4 you are talking to a PIA so it is a true
parallel output situation.  You will not have to worry about any "helpful"
buffering of the commands you send out.  Also, this will leave the P: port
free to run a Centronics-type printer if you so desire.

Good luck.

-John Sangster
jhs@mitre-bedford.arpa

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mmb3538@ritcv.UUCP (01/29/87)

In article <8701261739.AA17227@mitre-bedford.ARPA> jhs@MITRE-BEDFORD.ARPA writes:
>I would suggest that you consider using the joystick ports to output commands
>to the robot as an alternative.  I think on an 800 $D301 controls the 3rd and
>4th joystick outputs, which have 4 bits of output each.
  
    Yes and no A bette choice and the one I used is to control the robot out
  of port 1 via joystick, and port two for line to the robot. Its been about
  three years since I worked for Atari, on robots - yes they were planing to 
  release one for 129 +- and it had a remote  control. You could
  pick up a set of atari remote control, throw tinfoil around the case and they
  will work great for interfacing to the robot. With one joystick port you can
  set up the use of 4 motors plus foward and reverse. I used a resistor, then
  a 2n3904 transisor then a 12 volt relay  to control the motor , You could use
   a 555 - 556 timmer instead of the relay. If you ave any other questions just
   reply to me I could dig up a circuit if you really need one. I did work 
   with the person who posted articles in antic a while ago( about 2 years)
   If you are having doubts about what language to use then try to use PNS forth
  it is perfect language for robots.