most popular microcontroller?

sorry, bad link. the fames mess it up. this is the one I was talking about:
http://www.olimex.com/dev/pic-p40.html
or do you think I should go with a 28 pin? I can get them both for the same price, and since the microcontrollers themselves are cheap, I figure "why not?"

what do you think? should I get it?

 

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That Olimex board is only for 40 pin types. It won't program any other size without an adapter. It's not really a programmer, it's an inexpensive breadboard that is programmable.

I like parallel port programming because it's compatible with 5 volts.

This I think is still a good place to start: http://www.covingtoninnovations.com/noppp/

Look at how the programmer works and look around for other plans. I don't know if you want to start with just the basic 16F84A type. If you do, the more modern version is the 16F628A. In spite of Covington's claims, these are not that obsolete. Microchip has come out with an even dumber and cheaper chip that is still fast and suitable for many applications.

I have to get busy with something. A little later I can give you some advice on how to tweak the NOPPP so that it actually works. The best thing about this is that it does enable in-circuit programming on your breadboard.

 

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I know, thats why I said "or should I..."

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hmm, what is the difference? I used a Motorola 68HC11E9 (talk about out dated). I simply compiled my C code into a .s19 and loaded it on via a program called Hyper Terminal. I would like to have a similar system with whatever I buy. I am sort of new to setting up a microcontroller. the one I used was set up and ready to go.

 

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The difference is that it is slightly more difficult to use the breadboard to program your experimental chips. If its price is satisfactory to you, have at it. The link I gave you has a workable programmer and links to David Tait's site, which has one that works through the serial port. The download includes the schematics.

What I used to do was hotwire Covington's NOPPP so I could work it without removing the chip from the breadboard. I was using the 16F84A. It's a good idea to put resistors in series with B6, B7, and the MCLR. Those are CMOS inputs. They don't draw any real current. You can finagle what you want to do with the 5 volt supply, but you have to turn it off and then on again to reset the chip before programming. Also, when programming, the PIC chip must not have a large power supply capacitor attached to it. There's some kind of problem that can occur if the power supply voltage rises too slowly.

Covington's site has a link to Windows software for the programmer. He also mentions a $49.99 development system from Microchip that includes a C compiler. Here is the link that works:Pic Kit 2 Don't use "Buy It Now." Scroll down the page.

 

I am still fuzzy as to what "more difficult" means.

so I should use a battery pack while programming?

 

It will be more difficult because that board does not come with any LEDs or Switchs. For the money, you'd be better off with something else unless I've missed something there.

You can used a power supply (either take the side of your comp. case off and hook into the PSUs power with crocodile clips, or buy one for £10 as you'll need to anyway with something like the Velleman). PICs come with all kinds of fancy powerup options like brown-out detect and powerup timer to ensure an acceptable working voltage is maintained before running. In the case of the Velleman, an on-off switch is present, so there will be no power discrepency as the capacitor charges intitially, so long as you don't turn it on within a few ms of plugging it in!

If you really want to use PIC18 ranges go for the easyPIC thing. That looks awesome (esp. with the graphical display option) as it can obviously program many types of PIC.

The Velleman K8048 is really good for getting to grips with PICs. It's also good soldering practice if you get the non-ready made version. With the supplied software in addition to MPLAB and the HI-TECH PICC ansi C compiler (student version) you learn the basics for a mere £20 (+soldering, delivery, etc. etc.).

I may even get one of those easyPIC or easyPICds demo boards myself, acutually. Trouble is, I've spent too much money on electronics recently!

 

I can get this one:
http://www.olimex.com/dev/pic-p40.html
for $19 shipped on ebay, fully assembled. i can solder well, I don't really need practice. I can solder surface mount stuff. =]

couldn't I just put my own switch on it? moreover, why do I need the LEDs? if I can find a program to compile my C code into the right format, and a program to load it onto the chip, I don't really need anything else.

 

The LEDs are to simulate outputs. You could just add whatever you want to that board separately I suppose.

One thing though, ICD2 is really useful. The K8048 does not support ICD2.

 

Interrupt the line between the big capacitor and the processor to reset. Make sure you have something like a .1 microfarad capacitor across the processor too. When the program tells you to insert the chip into the programmer, interrupt the line with a switch or whatever you like, then turn it on again. If the programmer is not NOPPP, you might have to do something different.

The difficult part comes in when you realize that you will probably want to use a solderless breadboard to work out a lot of your circuits. You really won't want to keep moving it back to the programmer all the time. Whatever programmer you use, you can run the ground, the 5 volt supply, and the data lines to the chip. Just solder them to the breadboard/programmer and run them the way you like them. The breadboard is just fine too. I was thinking that you could use your favorite design from the net and just use junkbox parts.

Here is something that might help a lot of programmers: I don't think that the capacitors on the lines from the parallel port help anything. I couldn't get the NOPPP to work with them, but it worked find without them. Another trick is that a lot of these chips default to low voltage programming mode. You can use five volts where it says 12.5 volts. Don't take my word, check. Also, there is a slight chance that your parallel port is of the open collector type, something you won't see these days. Then you will need the resistors on the line for pullup.

 

I see your point about wanting to use a solderless breadboard. perhaps I should buy this:
http://www.sparkfun.com/commerce/product_info.php?products_id=21#
and simply cut off the excess board on the upper left, and attach 2 edge connectors (or whatever they are called) to the I/O pins via some data ribbon. then I can connect the I/O pins to a breadboard easily and consistently.

 

p.s. it is ICD compatible (I am not so sure about ICD2, I will have to look into it.

 

This one looks like the only one that includes an onboard programmer and it looks like that programmer can be cabled to the other boards with the cable you can also buy. You can also cut one of those cables to use with a solderless breadboard if you'd rather.

 

yeah... I am still not sure what an on board programmer is. I mean, I know what it does- allows you to load and run your programs without removing anything. but, how would one program a chip without an on board programmer?

also, I would like more than 18 pins, either 28 or 40. that way I will never need to upgrade.

 

The ones that don't have an onboard programmer either require that you hook the board up to a programmer or that you program the chip on a programmer then move it to the board.

The trouble with buying any particular pin count is that you are stuck with that unless you buy another board. So figure out which one you want and buy that.

 

this one looks good, but I would like more pins.

 

this one! looks good. I don't see any reason to dislike this board, but if there is some reason, let me know.

 

It looks like it has everything. You see, any circuit you build using any of the flash programmable PICs can use the ICSP standard, but you may have to fiddle iwith it a bit. Just figure out how to get to the data I/O pins, the reset, and 5 volts and ground, and how best to prevent overloading the +5 volts from the programmer. I used to use ICSP from a homebuilt programmer to program right on the solderless breadboard. There isn't much to it.

The programmer on Ebay has a six pin connector for ICSP. It also fits all PICs with legs on them. If I were you I would get an extra cable and fix it to use with solderless breadboards. You also want to make sure that the pinout of the cable matches the boards you use, or build an adapter.

 

That is the one you can run a cable from to any of the other boards that they can sell. The other boards won't program the chip unless you use that cable. The others will.

 

what? you confuse me with your use of "others" =]

I was thinking of using 2 20pin ribbons, and either close them in the ZIF, or solder them to the bottom. that way they will always be in the same order as the chip's pins, and I can attach it to a solderless breadboard (or whatever).

 

Well I know that I think I thought I said, or something like that

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Do what works for you. The Sparkfun breadboards have the six pin connector on them. They can be run to the PG-4 board and programmed through it. The one on Ebay has the same kind of connector but I don't know if it has the same kind of pinout.