This robot was a pain in the butt. Fortunately, one of the manuals is annotated. The project was to talk to Judith, a Pro Arm RS2200 through arduino. Looking at the protocol it SEEMED easy, but the real challenge was how much was going on the behind the scenes in the proprietary software that runs on an apple IIe? Fortunately for me, not much. Keep in mind this did not take one evening.
I build a shield that connects to the parallel port in the back of the robot via its apple cable. It was straight through. I connected strobe pin 1 to Arduino DIO 2. then the D0 on the robot to DIO 3 on the arduino etc. I kept 1 and 0 open on the arduino because I need the usb connection. with Error on 11, Ack on 12 and Busy on 13, I can set the pins, and then toggle the signal pin, then set the next set of bits. I had a huge issue with the movement command, just keep in mind there is a space between M and the numbers, and those are all commas between the numbers so M 0,0,0,0,0,0 is a valid command. if you screw it up the error light will let you know.
The other issue is the problem of endedness. so to send the open gripper command, you send O, but you send it like 01001111. But then it just waits on you. you need a linefeed and cr 00001010 and 00001101 keep in mind each of these are clocked into the robot. so you set the DIO3-10 to 01001111, toggle pin two then set the bits to 00001010, toggle pin two, set the bits to 00001101 toggle pin two. For a brief moment you wonder why you didn't hear anything and then realize the gripper was already open.
such is life.
for my next trick I'll have to repair her because she broke her claw cables. I have some cable for that, I just don't know where.
No comments:
Post a Comment