perhaps under linux or some specifically rtos environment where you could control specific processes assigned to cores you have a decent chance of this. but under any smp aware ms os that I know about this would be a very difficult task.
I see what you’re saying. Even though you only pulse an R/C servo once, every 20ms frame, you’d still be updating the parallel port buffer at perhaps a microsecond rate. But not necessarily every us. Still nasty!
An SPI interface would help (as in the SSC32), but then you might as well use the SSC32!
If only 8 R/C servos needed to be updated, it might be worth it.
Alan KM6VV
What I don’t understand is why would you want to do all this when you could just use an SSC-32?
lol, when you don’t have much spare cash around for hardware then a software solution utilizing what you do have on hand merits at least examining as an option.
frequently people fail to ask the important questions about personal determination, what value per hour they assign to their time, and equally important either lack the knowledge or skill to estimate the amount of time involved in a project to support a realistic viewpoint when considering the first two partsd of the question.
it is an interesting question, whether a small laptop could be made to directly control a few servo outputs using something like a parallel port, and that is what we’ve been discussing around. while there may be enough hardware in a pc to support the exercise it should be pretty clear at this point that a non windows OS is pretty much a given and a solid aptitude in programming either low level ms dos type code or extreme aptitude in programming for a linux environment will be required to do a decent job of it.
personally I’m waiting for someone to ask why it can’t be done in java or c# or some other ridiculous language just so we can all have a good laugh until we barf session. 
The hanger flying so far appears to be based on a possibly flawed assumption that the origional question above actually asked how to control an RC servo using a laptop or pocket pc, which may not be the case. 
This was the original question. Use the PC as the controller of the robot.
So without saying how many R/C servos (somewhere we understood that R/C servos were to be used), the simple answer (with a lot of work) would be a yes. Is it the “best” way? Depends on the time/money/experience equation! I’m partial to using a microcomputer to run my R/C servos (i.e. SSC32). but I could see directly using a PC control program with say, only 8 (12?) R/C servos to control.
I may even write a simple code module to test my assumptions sometime, and drop it into a copy of my CNC controller software.
Might be fun!
Alan KM6VV
Probably a better answer would be that if the pc is fairly modern, the addition of several inexpensive parts, such as an ssc-32, a wifi adapter and a webcam, the pc could make a good controller for the bot. If the minimum external parts are desired, then if the pc has a parallel port and an analog game port, then a lot things could be done with some additional effort.
So , what i cannot understand is that: laptop will transfer new programms to the robot all the time?and i will have a programm running on the laptop?
Sigh…
I don’t think you understand how all this stuff works. I think you seriously need to back up and start with the raw basics. Buy a few books that explain this stuff. Both the laptop and the MCU are going to need some sort of software to perform a specific task… agree? 
oh and one post is all you need, not two.
Can you tell me any tutorial?
please check this:
I cannot understand some things and i am totally confused.I have spend many hours on my pc looking for help.
So , i would like to make a robot using my laptop and SSC-32 servo controller . I havenot work with such thing before. As i have understand till now ,I will have a programm in my laptop that will control the servos.
If i am wrong please correct me.
So my question is :
- In which language will i build the programm?
and - Can you give me any link to tutorials? I need a tutorial for the serial communication.
there is no need to cross post on this forum. quite honestly it just confuses the people trying to help since the information and replies are not all in one thread.
before trying to pick a programming language and plow headlong into tutorials and application development may I ask if you have an ssc-32, a couple servos, and battery to work with? the reason I would ask is if you download the lynxterm application, read through the ssc-32 user manual, hook up the ssc-32 and a few servos, and play with sending some commands manually to the ssc-32 through lynxterm you will gain leaps and bounds of insight into what a program needs to do to control servos.
it will also help to think a little bit beyond controlling servos and consider what type of input, sensors on the robot or joysticks on the pc as examples, your program would need to function. when you have a rough idea of these things you can take a more informed look at how you would go about writing a program. which specific language probably isn’t nearly as important as how easy it is for you to understand how to program and be able to think out logically how to make the program do what you want.