what kind of microcontroller should i get?

[Shaddy Daddy]

Hi,

I require to be able to control two motors for a finite period of time
(ie, 4 minutes), from say a joystick, then input some values into the
microchip-microcontroller based on the positions of the motors. I
then want to disconnect the joystick and have the motors run on
automation based on these values. Would i have to have a joystick and
microcontroller hooked up to the computer first, then disconnect the
microcontroller and have it run on its own?

I want an ideally low power source...

what type of microcontroller should i get? what brand name...?


Thank you so much in advance!!!

 

[Robert Monsen]

Hi,

I require to be able to control two motors for a finite period of time
(ie, 4 minutes), from say a joystick, then input some values into the
microchip-microcontroller based on the positions of the motors. I
then want to disconnect the joystick and have the motors run on
automation based on these values. Would i have to have a joystick and
microcontroller hooked up to the computer first, then disconnect the
microcontroller and have it run on its own?

I want an ideally low power source...

what type of microcontroller should i get? what brand name...?


Thank you so much in advance!!!

This sounds like a neat idea. However, its going to be a bit of work to
implement. I know of any off the shelf solution for this, which means you
are probably going to have to build it.

Are you still interested?

Regards,
Bob Monsen

 

[Ian Stirling]

Hi,

I require to be able to control two motors for a finite period of time
(ie, 4 minutes), from say a joystick, then input some values into the
microchip-microcontroller based on the positions of the motors. I
then want to disconnect the joystick and have the motors run on
automation based on these values. Would i have to have a joystick and
microcontroller hooked up to the computer first, then disconnect the
microcontroller and have it run on its own?

I want an ideally low power source...

what type of microcontroller should i get? what brand name...?

Practically any micro can do this, it's all in the programming.

You don't sound like you have much knowledge about programming.

There are I believe industrial controls that can do this.
alt.machines.cnc would know, though it's not the right group.

--
http://inquisitor.i.am/ | mailto:[email protected] | Ian Stirling.
---------------------------+-------------------------+--------------------------
"Melchett : Unhappily Blackadder, the Lord High Executioner is dead
Blackadder : Oh woe! Murdered of course.
Melchett : No, oddly enough no. They usually are but this one just got
careless one night and signed his name on the wrong dotted line.
They came for him while he slept." - Blackadder II

 

[Frank Buss]

I require to be able to control two motors for a finite period of time
(ie, 4 minutes), from say a joystick, then input some values into the
microchip-microcontroller based on the positions of the motors. I
then want to disconnect the joystick and have the motors run on
automation based on these values. Would i have to have a joystick and
microcontroller hooked up to the computer first, then disconnect the
microcontroller and have it run on its own?

You can use for example a PIC microcontroller: http://www.microchip.com
Which one depends on how much data you need to store. If 128 bytes are
enough, you can use the cheap 16F628. If you want to store more, you can
use the 18F252 (I'll use this for my project, too). You can use the 32 kb
flash memory for storing the position data (minus the program, which should
fit in some 100 bytes).

 

[Wouter van Ooijen]

what type of microcontroller should i get? what brand name...?

My favourite selection algorithm for newbies:
- start with PIC, AVR, 8051, 68HC, 430 and everything else that I
forgot
- leave out anything you can't actually get hold of
- look around for help, and from the remaining chips select the one
your helper is most comfortable with

rationale:
- a nice chip is no good if you can't get it
- help is more important that technical merits

and reading http://www.voti.nl/swp won't do any harm.



Wouter van Ooijen

-- ------------------------------------
http://www.voti.nl
PICmicro chips, programmers, consulting

 

[Shaddy Daddy]

Thanks!

I am a graduating electrical engineer from university of toronto, so I
would be able to figure out how to program given given the necessary
tools.

I see that the size of the program is a factor in determining which
microcontroller I should buy. However, I'm not sure how large the
program will be. Can I write the program and then determine its size,
then choose the appropriate microcontroller?

I am interested in mass-producing the mechanism, so cost of the
microcontroller is an issue.

What platform is used to write the program? How can I get examples of
programs?

Also, can these microcontrollers accept a variable voltage source as
their power source, (ie, solar cells from a calculator?) what would be
an ultra-cheap method of a power source in this case, if not
calculator solar cells?

Thanks in advance!!

 

[Frank Buss]

I see that the size of the program is a factor in determining which
microcontroller I should buy. However, I'm not sure how large the
program will be. Can I write the program and then determine its size,
then choose the appropriate microcontroller?

Yes. You can use the free MPLAB for example, write your program and
compile it to see how big it would be. Nice feature in MPLAB: you
can emulate the whole chip with your program on the PC, with simulated
IO:

http://www.microchip.com/1010/pline/tools/picmicro/devenv/mplabi/mplab6/index.htm

I am interested in mass-producing the mechanism, so cost of the
microcontroller is an issue.

What platform is used to write the program?

I'm using MPLAB with PIC-Start+, but there are less expensive development
platforms available from other companies.

How can I get examples of programs?

Just browser the Microchip site. A starting point:

http://www.microchip.com/1010/suppdoc/appnote/index.htm

Also, can these microcontrollers accept a variable voltage source as
their power source, (ie, solar cells from a calculator?) what would be
an ultra-cheap method of a power source in this case, if not
calculator solar cells?

Yes, read the datasheets:

http://www.microchip.com/1010/pline/picmicro/index.htm

And of course, there are some other very good microcontrollers from
http://www.ti.com/ and http://www.atmel.com .

 

[Shaddy Daddy]

Thanks,

Not to belabour the point, but I have a few more enquiries...

I also need to add a clock to the microcontroller, to be able to run a
motor continuously during the day...

is this at all possible...?

will it increase the size of my program dramatically...?

can i get a readily available function to impliment this?

what would be the approximate size a program containing a clock and
interface for joystick movement as well as storing a few 'double'
variables, ie 5.

thanks,??

can anyone direct me to a similar joystick input program, or realtime
clock program?

THANKS!!!

 

[Shaddy Daddy]

also, can anyone recommend a brand of motor to link to the
microcontroller once it has been programmed?

also, do i have to add any info about the brand of microcontroller in
the program,

also, how do i connect the two!


THANKS!!!

 

[[email protected]]

Hi,

I require to be able to control two motors for a finite period of time
(ie, 4 minutes), from say a joystick, then input some values into the
microchip-microcontroller based on the positions of the motors. I
then want to disconnect the joystick and have the motors run on
automation based on these values. Would i have to have a joystick and
microcontroller hooked up to the computer first, then disconnect the
microcontroller and have it run on its own?

I want an ideally low power source...

what type of microcontroller should i get? what brand name...?


Thank you so much in advance!!!

Your requirements seem to be commercial, if so, you will need a lot of
money because a-lot-of-time you won't get. So because you are trying
to avoid cost, you are doooomed!

If you play with MPLAB, as suggested above, you will soon get a feel
for what's in store for you for "free". By the time you have produced
some sort of program and realise you need more ram, you discover that
you have used the wrong language and need to begin again in C; then
you need to learn C.

If you are doing this as a hobby/exercise then why not, that's how I
started.

Robin

 

[Frank Buss]

I also need to add a clock to the microcontroller, to be able to run a
motor continuously during the day...

Sorry, but if you are a graduating electrical engineer, it should be
possible for you to read the PDF datasheets from the Microship site and
yes, it has more than one clock.

is this at all possible...?

will it increase the size of my program dramatically...?

can i get a readily available function to impliment this?

No, you have to work on your own, otherwise you can contact me per eMail, I
can do it for you for normal hourly rates.

 

[Ben Pope]

Hi,

I require to be able to control two motors for a finite period of time
(ie, 4 minutes), from say a joystick, then input some values into the
microchip-microcontroller based on the positions of the motors. I
then want to disconnect the joystick and have the motors run on
automation based on these values. Would i have to have a joystick and
microcontroller hooked up to the computer first, then disconnect the
microcontroller and have it run on its own?

From your comments, you seem to know nothing of programming. And little of
electronics.

This is not going to be a simple task for you - the field of programming and
electronics are not simple.

Ideally you will need to learn to pragram in C, as thats the most widely
used language for this type of task.

Once you have an idea of how C works, and of how microcontrollers work, you
should be able to interface a standard PC joystick and understand how to
control the motors.

Depending on the accuracy required, I suspect you'll want stepper motors.

I don;t suggest writing the program, finding out how big it is and then
choosing a micro... many PICs and other Micros are pin-compatible (within
their own range) so choose a cheap one, build yourself a programmer (or buy
a kit) and start learning.

If you're a quick learner and it makes sense to you, it might take you 500
hours with a very simple microcontroller. Do you guys think thats a
reasonable estimate? Difficult to say really...

Ben

 

[Frank Buss]

If you're a quick learner and it makes sense to you, it might take you
500 hours with a very simple microcontroller. Do you guys think thats
a reasonable estimate? Difficult to say really...

That's 3 months, if working 8 hours daily. If you know nothing about
programming and electronics and you don't do it every day, you need a
multiple of this time, I think. If you have expierence with it, this
project would be a one week project.

 

[Ben Pope]

That's 3 months, if working 8 hours daily. If you know nothing about
programming and electronics and you don't do it every day, you need a
multiple of this time, I think. If you have expierence with it, this
project would be a one week project.

My initial estimate was 500-1000 hours. I really have no idea how long it
would take somebody to learn enough to do this project - I agree that with
somebody experienced it shouldn't take longer than a week.

It would probably take me a couple of weeks... my hardware knowledge isn't
as strong as my software. And a little while to decide parts.

Ben

 

[Tim Shoppa]

Also, can these microcontrollers accept a variable voltage source as
their power source, (ie, solar cells from a calculator?) what would be
an ultra-cheap method of a power source in this case, if not
calculator solar cells?

The microcontrollers themselves can draw very little current (although
tailoring the brownout response may be necessary for your vaguely worded
application). The killer will be running those motors that you mention -
you're probably looking at a few 100mA or so at a few volts, and the cost
and size of a solar panel to run such motors (including the
gotcha that it will only work in direct sunlight...) will bite you
hard.

Using solar panels to charge nicads which then have the ability to run the
motors for a few minutes a day might be more feasible, but if cost is a
constraint you wouldn't be charging batteries with solar panels. Is there
some other constraint that makes solar cells the preferred solution?

Tim.