View Full Version : help!!!!! roborealm with basic stamp 2

07-09-2006, 11:03 PM
i am making a project where i want to control 2 servos via the pc in real time but i dont have a servo controller.

can i move them without the module?

enlight me

sorry for my bad english

lazyman from greece

p.s. i am despared


Post Edited (lazyman[GR]) : 7/9/2006 7:13:05 PM GMT

Kevin Wood
07-10-2006, 03:45 AM
How exactly do you want to control the servos from the PC?

Are you:
1) trying to use only your PC and the servos, with no other electronics

or are you:
2) trying to interface your PC to a BS2 that is connected to the servos?

If the answer is 1, you'll need an appropriate interface cable (you'll probably need to build one), and some application (you might have to write one) that allows for servo communications.

If the answer is 2, you can connect your servos to a BS2 module, and write a program that does the following:
1. Listens for input from the PC (easiest would likely be serial port)
2. Receives and parses input from PC
3. Performs some task based on PC commands
4. Goes back to Step 1

Also, just to let you know, when posting questions, it's easier for people to help when you give as much detail as possible. Let people know what parts/components you have, and what exactly you are trying to accomplish.

07-10-2006, 05:44 PM
i want to control a camera via a laptop.
i want to move it left-right down-up

the program it may have 2 selections.
fully automatic. use of roborealm to lock on target (can iˇuse external variables to the pbasic program likeˇroborealmˇ?ˇ)
manual (at first step with serial cable)
at last step with rf communication.

ps. can i control more than 2 servos with basic stamp using bread board?
thanx for the answers


Post Edited (lazyman[GR]) : 7/10/2006 3:10:37 PM GMT

Ryan Clarke
07-11-2006, 12:40 AM
Depending on what you need to do and how fast, you can use multiple servos with a stamp and breadboard- consider: a servo has a refresh 'window' of approximatley 20 ms - so clever use of that refresh window allows for control of multiple servos....


Ryan Clarke
Parallax Tech Support

RClarke@Parallax.com (mailto:RClarke@Parallax.com)

07-11-2006, 01:42 AM
can you give me some lines of source code to control the 2 stantard servos via pc with pbasic?
that can be usefull for me



07-11-2006, 05:38 AM
can i also put variables (like from a *.txt) from a third party program like roborealm???


07-17-2006, 12:59 AM
You'll need a module like the Parallax Servo Controller http://www.parallax.com/detail.asp?product_id=28023 to control the servo if you are not using a BS2 module. The board is capable of receiving commands directly from a PC via serial and passing them onto the actual Servo motors that understand PWM. You cannot connect a PC directly to a servo ... the servos and PC just do not speak the same language. If you get that board then you can then use a PC and RoboRealm to control the servo via the board as needed to get your pan/tilt camera to work.

Let us know if you have any more questions.


Chris Savage
07-17-2006, 09:30 PM

ˇˇ A better suggestion for connection to a PC is Stock# 28823, since it is USB, whereas 28023 would need additional circuitry to connect to a PC Serial Port.ˇ The USB Version communicates serially just as the 28023 through a VCP Driver installed on the PC.ˇ Please see the documentation for more information.ˇ Take care.

Chris Savage
Parallax Tech Support
csavage@parallax.com (mailto:csavage@parallax.com)