Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: nckspec on March 25, 2008, 09:35:54 PM

Title: Choosing a microcontroller
Post by: nckspec on March 25, 2008, 09:35:54 PM
Hello, is there a microcontroller that can be programmed in a very basic language and output more than 5v?
Title: Re: Choosing a microcontroller
Post by: AndrewM on March 25, 2008, 09:39:56 PM
Sorry, have to ask... Why do you want to output more than 5V from a MCU?
Title: Re: Choosing a microcontroller
Post by: nckspec on March 25, 2008, 11:14:24 PM
i thought that it would be faster but now that i think about it, it would probably be fast enought with 5 volts.
Title: Re: Choosing a microcontroller
Post by: superchiku on March 26, 2008, 06:51:52 AM
many mcu's can be programmed in Basic just look in google
Title: Re: Choosing a microcontroller
Post by: Trumpkin on March 26, 2008, 09:22:21 AM
Quote
Hello, is there a microcontroller that can be programmed in a very basic language
I don't think he meant is there a microcontroller that can be programmed in BASIC I think he meant is there a microcontroller that can be programmed in a language that is easy to learn. I'd say C is the easiest thing to learn for beginners. You could use C with the Arduino and Robostix augmented microcontrollers and anything else that has an AVR microcontroller.
Title: Re: Choosing a microcontroller
Post by: nckspec on March 26, 2008, 02:21:21 PM
what would you suggest that would help me learn c. I've tried it before and it was kind of difficult.
Title: Re: Choosing a microcontroller
Post by: airman00 on March 26, 2008, 04:50:56 PM
what would you suggest that would help me learn c. I've tried it before and it was kind of difficult.

search online for tutorials and reverse-engineer other people's work
Title: Re: Choosing a microcontroller
Post by: paulstreats on March 26, 2008, 05:47:55 PM
Learning c for microcontrollers is a lot easier than learning it for computers because you only use the vary basic parts of the language.

Quote
i thought that it would be faster but now that i think about it, it would probably be fast enought with 5 volts.

ps. the voltage doesnt define the speed of the microcontroller ;)
Title: Re: Choosing a microcontroller
Post by: nckspec on March 26, 2008, 10:40:05 PM
thank you for pointing that out about the voltages because nobody could really explain to me the purpose of voltage. Does amps effect how fast it goes.
Title: Re: Choosing a microcontroller
Post by: AndrewM on March 27, 2008, 07:22:38 AM
If you are talking about how fast the microcontroller goes, then no.  The microcontroller manufacture determines how fast it goes based on clock cycles and frequency.  If you are talking about how fast the robot goes, as in the motors, then you need to realise that you should not power your motors through your microcontroller, so the microcontroller voltage and/or current have nothing to do with robot speed (at this point).  A seperate power source should be provided for your motors, and how fast they go is a mix of motor RPM per volt, motor torque, gearing ratios, wheel size, and yes, current (but only so far as a required amount of current must be available to keep the motor out of a stall).
Title: Re: Choosing a microcontroller
Post by: nckspec on March 27, 2008, 09:20:43 PM
also is their any difference in writing c for the avr atmega8
Title: Re: Choosing a microcontroller
Post by: Webbot on March 27, 2008, 10:26:38 PM
Since there ain't no keyboard, and no screen (let alone graphics card), no sound card etc then it makes coding a micro-controller easier. Once you get the hang of variables, for loops, while loops, and if statements then thats all you need. Try looking at the sample code in things like the $50 robot tutorial. Its always easier to look at some existing code and then learn by changing it a bit at a time rather than starting with a blank sheet of paper. Its all down to playing and experience.
Title: Re: Choosing a microcontroller
Post by: winnie on April 03, 2008, 08:57:30 PM
since this is about a microcontroller thread..

can you suggest microcontrollers that are both capable of collision avoidance and path tracing?

we are just starting from our robotic projects and we want to have a robotic car.. i inquire on some individuals and he said that there is not yet an available microcontroller that is capable of both function but i believe that it is not on the microcontroller but on the program itself.. but still we can't afford to waste money buying unnecessary microcontrollers or a microcontroller that is not appropriate we know a little C++, C#, and Java but not that smart..

I hope you can help us... :)
Title: Re: Choosing a microcontroller
Post by: AndrewM on April 03, 2008, 09:05:30 PM
By path tracing are you referring to following along a line or recording the path the robot takes to get from point a to b so that it can retrace its steps?

Just about any of the microcontrollers available can handle collision avoidance:  basic stamp, atmel, parallax propeller, pic, etc, etc.  It really is all in the algorythms used (progamming).  Seeing as you know a little C (or atleast its object oriented successors), I would recommend an atmel or pic, but would lean you toward an atmel as programming one is far cheaper than a pic.
Title: Re: Choosing a microcontroller
Post by: michaelsane on April 03, 2008, 11:56:44 PM
Take a look at microchip.com and get some sample PIC's.  Also you will need to buy or build a programmer.   I am currently programming with the Pic 18F series with Microchip's C18 compiler (free student edition).  Its really simple to learn, and there are good tutorials available online.  When choosing a microcontroller you should try and choose a controller that will meet your needs as far as I/O, timers, and hardware peripherals.  However you may want to go the route of making your own mcu (augmented, meaning a PIC with all of the pins connected to large pins which you can connect sensors, servos, etc...).  I am working on my own mcu right now and will post some schematics if you are interested. 
Title: Re: Choosing a microcontroller
Post by: Admin on April 06, 2008, 01:29:15 PM
http://www.societyofrobots.com/robot_faq.shtml#best_microcontroller
Title: Re: Choosing a microcontroller
Post by: winnie on April 10, 2008, 11:55:55 PM
in our path tracing the robotic car will follow a line of a specific color we're still not sure if it's black or white though..


are only PICs can be augmented? I think that's what we need

and also in our research some of the microcontrollers are not reprogrammable(it was mentioned that you can only program it once) we don't want to buy that kind of microcontoller..
Title: Re: Choosing a microcontroller
Post by: airman00 on April 11, 2008, 12:30:03 PM
are only PICs can be augmented?

no any microcontroller can be augmented

first pick a programming language, then pick a microcontroller that runs that language
Title: Re: Choosing a microcontroller
Post by: winnie on April 16, 2008, 02:35:39 AM
I am working on my own mcu right now and will post some schematics if you are interested. 


where can i find your post?
Title: Re: Choosing a microcontroller
Post by: winnie on April 17, 2008, 12:33:15 AM
Does it matter if the pins used are less or more than required? How would I know how many pins to use?
Title: Re: Choosing a microcontroller
Post by: JAy1st on April 17, 2008, 12:49:33 AM
Quote
Does it matter if the pins used are less or more than required? How would I know how many pins to use?

More there is , bigger the µC.

You first have to figure out what you want exactly, how many sensors and actuators...

Title: Re: Choosing a microcontroller
Post by: brickbob on April 17, 2008, 03:18:36 AM
Try This

www.parallax.com.

you can choose asm, basic, java or spin.

Sorry admin just to help these feller.
Title: Re: Choosing a microcontroller
Post by: winnie on April 17, 2008, 09:10:57 PM
Quote
Does it matter if the pins used are less or more than required? How would I know how many pins to use?

More there is , bigger the µC.

You first have to figure out what you want exactly, how many sensors and actuators...




how many pins are required for each sensors?
Title: Re: Choosing a microcontroller
Post by: winnie on April 17, 2008, 10:03:33 PM
We're actually  choosing between PIC24FJ and dsPIC33FJ... Are they too much for a simple project?
Title: Re: Choosing a microcontroller
Post by: GHF on April 18, 2008, 08:13:49 PM
We're actually  choosing between PIC24FJ and dsPIC33FJ... Are they too much for a simple project?

I'd recommend the lower series -- specifically 16F88 or 18F2550 for simpler projects just because you have much less complexity to deal with. I mean, do you really want to configure 34 different options in the configuration fuses when you just want to move a servo? But, you don't want to go too simple, like the ancient (but trusty) 16F84, because you want a more recent one that has more code space, RAM, and hardware peripherals. HW peripherals like the USART or CCP module make interfacing with things a lot easier and faster than if done in software.

Also, have you thought about what compiler and programmer you're going to use with the 24F and dsPIC? Neither will come cheaply, but compilers for the 16F and 18F are oftentimes free, and the programmers are next to free.

-Xo W.
Title: Re: Choosing a microcontroller
Post by: winnie on April 19, 2008, 01:12:21 AM
We're actually  choosing between PIC24FJ and dsPIC33FJ... Are they too much for a simple project?

I'd recommend the lower series -- specifically 16F88 or 18F2550 for simpler projects just because you have much less complexity to deal with. I mean, do you really want to configure 34 different options in the configuration fuses when you just want to move a servo? But, you don't want to go too simple, like the ancient (but trusty) 16F84, because you want a more recent one that has more code space, RAM, and hardware peripherals. HW peripherals like the USART or CCP module make interfacing with things a lot easier and faster than if done in software.

Also, have you thought about what compiler and programmer you're going to use with the 24F and dsPIC? Neither will come cheaply, but compilers for the 16F and 18F are oftentimes free, and the programmers are next to free.

-Xo W.


i think we have to buy a book "robotics for dummies".. i can't comprehend much about microcontrollers, especially robotics, but staying in this forum make it a lot easier for us...

we're actually the one to make the program about the project but we don't actually know if the microcontroller that we'll chose is appropriate with C++ language and the big problem is we don't have any idea how to transfer the codes to the microcontroller..