Hi!
I have an education from both hardware and software computer engineering, but I have only worked with software for many years now. I'm not up to date with what's what in the world of embedded systems now, so I hope someone here might point me in the right direction.
I have a little private pet project which required an embedded system. It is quite simple, but I don't know what CPU or kit to use. Here are some (short) specs on the system:
The CPU should control four small electric motors. There should be two buttons which the CPU gets input from. These buttons should be lit, so that the CPU can control if the light is on or off. There will be a small LED/LCD display of some sort, able to show at least 12 characters. The CPU must keep track of the date/time as the logic depends on time. Ideally the system should run for at least a month on a set of batteries. If batteries are a problem, plugging the system into the socket is possible, but batteries are ideal. During development, it would be great if the CPU was available via USB. I know a bit of asembler code, but if there was any way to program at a higher level (C is fine), that would be great! This is, as I said, a private project, so price on the components is an issue. I'm hoping that the components I need should be less than $100 and absolutelly below $200.
Can anyone recommend any components/kits/resources to help me get started with this project? If you can recommend CPU/kit, display, buttons, power supply or have any other tips, I would be most gratefull!
Chris.
hi Chris, now u just decide the task and the no of task u want to get complited form the controller then you go for the no of controller manufac.site decide which one is best suited for your operation read the data-sheet carefully and working on it as u r the developer and designer it is most importent for u to do this thing by yourself only bcoz final dession is only yours and any one is do not want to responsible for it.and only u r the person who know what kind of robo u are going to develope if u work carefully it will take only 2 to 4 days
sameer
Thank you for your reply. I know I am the one with the responsibility for my project, and I'm not looking for anyone to do the job for me :) I'm just looking for a few tips as to where to begin from people who know this field better than myself.
No body will done the u r job better than u but help u definatly if u r ready to give the all detail's regarding u r prog i will try form my side but it must be clear b'coz any one not that much time to read and understand all the thing's
If you are getting started with microcontrollers, you should look into simple 8-bit parts. A microcontroller from the '51 family might be a good idea, see http://www.silabs.com for a selection of excellent MCUs. But the '51 architecture comes from the 1980's and it has its quirks and limitations, although it doesn't stop developers from actively using them in many new designs. For a more up-to-date architecture see еру AVR family at http://www.atmel.com. The added benefit is the availability of free WinAVR toolset, so you don't have to invest into developing tools. Most modern microcontrollers have on-chip debug support. You should use it as it greatly eases debugging of your code in a live running system. You should think about what adapter you will have between the microcontroller and your PC running the debugger. Often you can get away with a simple wiggler-style adapter between a JTAG port and a parallel port of a PC. Wigglers can easily be made at home. Unfortunately, USB debug adapters are more expensive, with a price in the hundreds of dollars. From your description the code for your application could fit into 1 or 2 KB or ROM and 128 or so bytes of RAM. But you should choose a microcontroller with 4 KB or more of ROM and 1 KB or more of RAM. This will cost you an extra dollar or two, but it will save you lots of headaches while developing code as you won't be so constrained in resources, especially when writing in C. As for real-time clock, some microcontrollers have this facility with low-power modes with power consumption of a microamp or so. But you can always use a dedicated chip for that purpose.
Regards, - mike
Try MSP430 from TI. It is a great processor and ultra low power.
Ideally the system should run for at least a month on a set of batteries.
That's going to be awfully hard, maybe impossible. Supplying the CPU off a battery for a month would be reasonably easy --- but not LEDs, and certainly not four motors. Not for a size of battery that you're likely to be willing to use, that is.
Of the architectures on-topic in this forum, an 8051 with a low-power sleep mode is the most likely candidate to work.
Thank you all for very informative replies. I will look at the components you have mentioned. As for power and batteries, I failed to say how much work they would do. They would probably (all together) run for 10-20 seconds pr. day - maybe less. Would that make it more reasonable to run the system on batteries?