Need some experienced advice

[Melanie]

> What is a good solid chip that is cheap (comparable to the atmel chips) that will work for me.

This depends on the number of I/O's you need...

For up to 16 I/O's the cheap 16F628A is a good choice. (a) You don't need an xtal (unless you're doing async comms) because it works from it's own internal oscillator, and (b) it handles MCLR internally for you too. So all you need is a program, some volts and it works!

I'll go with skimask's recommendation... forget any and all training courses. Equip yourself with a good programmer, latest version of PBP, a handfull of PICs, the Datasheets are free, a breadboard, good PSU, LCD with flying leads on it, and you're in business.

If you don't know how to do something, then cobble together a little test program to display the result on the LCD. You'll learn more that way than any course.

[skimask]

I'll go with skimask's recommendation...

WHOA! Did I read that right! Did Mel go with MY recommendation? (head swelling, I'll let you know when the pressure gets to be too much )
Learned all I can, I have...but a Jedi, I am not...

I'd say go with a PIC18F4550 and associated hardware, programmers, etc.
You can get it in a DIP package (which means you can mess with it on a solderless protoboard), it's got plenty of I/O and memory, plenty of functionality, and it's got USB ports...which, no, they aren't really for a beginner, but they are there for future toys.

[bill12780]

I cant tell you how nice it is to get some good help as a noob on a forum. It is RARE! I read a sticky from Melanie about this and it must have worked!

I do appreciate all the suggestion on chips. I will get the datasheets tonight and look them over.

If you all can handle it. I do have more questions....

1) How big a problem is it moving from one chip to another. Example. Lets say I choose one chip and find I don't have enough space for the program. Are there "other" versions of the same chip with more memory? I mean pin for pin compatible? Otherwise, how do you even begin to estimate how big your program is going to be?

2) I mentioned my project is keypad based. Have any of you heard of or know what the advantages are to using a 74c922 keyboard decoder? I have seen other designs that dont use them and some that do? Like I mentioned before I am an electronics guy (mostly analog stuff) so I have never used a 74c922. I do understand that the decoder will reduce Inputs needed on the PIC and the debounce is controlable. I guess what I am asking is more from a "Coding" point of view/use with a PIC perspective.

3) What do you all think of the MEL lab-x1 dev board? I feel when making purchases its always best to ask the man(or woman) that owns one. Also, is my epic programer still gonna be ok with the new chips. Or should I invest in a USB programmer.

4) What about the PIC-AXE with the bootloader? If I am not mistaken would this not me similar to like having a Jtag port? As Ricky Ricardo would say "splain it to me"

Man, I cant tell you how refreshing it is to go to a forum and not get slammed for being ignorant...(Ignorant has in un-informed---not stupid that is different!)

Thanks again, and if anyone needs electronics help I will do my best!

Off to the MICRO-CHIPS website for some datasheets!

bill12780

[skimask]

1 - Piece of cake... Most of the PIC's in the same family are (i.e. 28 pin for 28 pin, 40 pin for 40 pin, and so on), 99% compatible at the pin level with a newer PIC having more functionality on the same pin or set of pins, about 95% compatible at the PBP level, and probably around 80% compatible at the assembly level. For instance, I built an MP3 player, started off with a 16F877A, moved to an 18F452, then an 18F4620. No change in hardware, and minor changes in the PBP source.

2 - The 74C922/74C923 aren't that easy to find anymore and they're a bit expensive. You could do the same thing with a much cheaper 18 pin PIC, and program it yourself to include things like shift keys, control keys and things like that. Can't do that with a 74C922...

3 - I don't own a dev board of any sort. There is nothing wrong with any of the boards sold by MeLabs, they're all good...however, I do believe you get a better deal with the ones from www.mikroe.com, the EasyPic4.
And I (and others will say the same thing) think one of the better programmers out there is the PICKit2, upgradeable, support direct from Microchip, it's USB, self powered, and so on. I just bought one, works great.

4 - PIC-AXE with a bootloader - all that means is that you can reprogram the chip without having a programmer, usually all you need is a serial port or something similar, but at the expense of a couple of pins and some code space. With time, you could make your own bootloader...or you could buy or download 'bootloader' code from various places on the 'net.

4a - and yes, it's similar to a JTAG port.

[b1arrk5]

I can highly recommend the LabX-USB board from ME Labs. It is set up for the 18f4550, so you can develop USB applications, it has RS-232 on board, and you can add things like Dallas 1-wire temperature sensors, etc. It has sixteen push buttons on it, so you can set up your keypad project right off the bat. It works with the EPIC programmer, but when I got my new computer I upgraded to the USB programmer, and am very happy with it. (It's getting hard to find an LPT port anymore.) The EPIC plugs right into the development board, you don't have to remove the chip to program it. I do like Melanie suggested, I output to the LCD to debug my programs, and there are a few LED's on the board if you just want to toggle something. I usually use one for a 'heart-beat' so I can tell if I screwed up and confused the microprocessor!

For quick one-off projects I like ME Labs proto-boards. I have one I put a ZIF socket on that I can put little chips like the 16f88 in if I want to try something fast and easy. Hope this helps.

Jerry.

[Pic_User]

Hi Bill,

Welcome to the forum.

3 - I don't own a dev board of any sort. There is nothing wrong with any of the boards sold by MeLabs, they're all good...however, I do believe you get a better deal with the ones from www.mikroe.com, the EasyPic4.
And I (and others will say the same thing) think one of the better programmers out there is the PICKit2, upgradeable, support direct from Microchip, it's USB, self powered, and so on. I just bought one, works great.

EasyPIC4 Development System $120
Get the accessories too while you are ordering.
http://www.mikroe.com/en/tools/easypic4/

Forum post example:
Development Board Recommendations
http://www.picbasic.co.uk/forum/showthread.php?t=5609

Forum post example:
keypad routine
http://www.picbasic.co.uk/forum/showthread.php?t=6230


“PICKit 2”, is one of the the best choices for a beginner, less problems with side-effects.

My opinions only.
-Adam-

[SteveB]

3) What do you all think of the MEL lab-x1 dev board? I feel when making purchases its always best to ask the man(or woman) that owns one. Also, is my epic programer still gonna be ok with the new chips. Or should I invest in a USB programmer.

I do own one, and I can not complain. Solid product. That said, I think the EasyPic4 is much more for the money. Lots of good feedback from those who own one as well. (I'm sure Steve, a.k.a. MisterE, will chime in here eventually).

SteveB

[mackrackit]

Hi Bill,

My 2.5 cents worth.

Dev board = Box of $4.00 breadboards from allelectronics.
Programer = PICKit2
Chip = 16F877A no USB though

[mister_e]

I do own one, and I can not complain. Solid product. That said, I think the EasyPic4 is much more for the money. Lots of good feedback from those who own one as well. (I'm sure Steve, a.k.a. MisterE, will chime in here eventually).

SteveB

YES indeed EasyPIC 4 all the way! And buy a couple of their EasyProto board adapter as well...

6 bucks it's nothing... it just don't worth to build your own now...

But yeah, assuming a tighter budget, PICKIt2, one breadboard and few parts it's a smart choice as long as the bill of material is at least under EasyPIC4 which should come with a 16F877A.

[bill12780]

OK everyone here is what I did.

I ordered my upgrade and manual for PBP (Should be here anyday)

I went with the Microe EasyPic4 with a few of the proto board adapters.

I have pretty much decided that I am going to use a PIC16f876 going to order some of those today.

I can not tell you how much I help you all have been. I would have been totally screwed if you guys had not spoken up and gave me some good info to work with.

I am sure once the coding begins I will be back. I will try and get in here every couple of days to see if I can help with any Electronics issues.

Thanks again! Its more appreciated they you know!

Best Regards,
Bill McFarland

[muddy0409]

I can not tell you how much I help you all have been. I would have been totally screwed if you guys had not spoken up and gave me some good info to work with.

I am sure once the coding begins I will be back

Hi Bill,
Yeah the folks in here are sure to be happy to help in any way.
Also, don't be at all afraid to ask some stupid question (that comes from experience, believe me!)

I've been a basic freak for yonks too, started with the VIC-20, remember them? Did some assembler with the 6502 but long since forgotten.

Anyway, enjoy the forum and the camaraderie(? spelling?) in here.

[skimask]

I ordered my upgrade and manual for PBP (Should be here anyday)
I went with the Microe EasyPic4 with a few of the proto board adapters.
I have pretty much decided that I am going to use a PIC16f876 going to order some of those today.
I can not tell you how much I help you all have been. I would have been totally screwed if you guys had not spoken up and gave me some good info to work with.
I am sure once the coding begins I will be back. I will try and get in here every couple of days to see if I can help with any Electronics issues.
Thanks again! Its more appreciated they you know!
Best Regards,
Bill McFarland

All good, solid choices... Just remember to start off simple (stupidlike? ) and work your way up. Play with everything, not only code, but config settings, learn how to manipulate them, mess with interrupts, get a button or two to work, move LEDs around (not the leds themselves, but the lighting thereof), talk back and forth with a PC thru the serial port...and so on and so on. Before you know it, we'll be asking you for answers...