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PJALM
- 22nd May 2008, 13:20
I am not sure if this is the right place to ask this but I'll ask anyhow.

My students are asking if they can make make a development board to learn all about making PCBs, programming micros etc. What would you recommend for the PIC that we can use on the board and what kind of features do you think they would most benefit from having onboard?

Any suggestions would be greatly appreciated. I understand we can just buy an existing board but they want to go through the process of making one so I thought it would be a good idea plus they would have something at the end that they can continue to learn from.

Thanks

Acetronics2
- 22nd May 2008, 13:44
Hi

this is a simple one ... for 18 pins Pics only.

always very useful for testing new pieces of code or commands ... even after 10 years .

Alain

PJALM
- 22nd May 2008, 15:01
Thanks for the reply and nice board by the way.

I want my students to make the development board themselves and not use and existing one. Instead I am trying to ask and see what a good PIC model would be to use as the base for the board and what kind of features would be beneficial to them to have included on board.

I was thinking something with Ethernet, USB, Can etc. built in so they can experiment with just about anything. We have our own PCB fabricating machines at the school so they will be doing the layout and fabrication themselves.

So far the only things I can think of adding are the following:

SD/MMC card reader (or maybe compact flash)
USB Host controller (like the one from FTDI)
USB Slave interface
PS/2 keyboard and mouse ports
LCD Display port (for character and graphic displays)
Matrix Keypad
Serial RS232/RS485 ports
On board Bluetooth and ZigBee
Ethernet or WiFi (using the XPort modules or built in Ethernet)
Gameport (for connecting joysticks)
Optical isolated Inputs/Outputs and/or relays
DAC and ADC modules
EEPROMS and/or flash memory
RTC

We considered adding a USB PIC programmer but all students are given a PICKIT2 so we will just add an ICSP port compatible with it.

I haven't been able to figure out what PIC to use that would be able to give us all this and yet still work with PicBasic. If you can think of which one may work I would be greatfull.

Thanks

tenaja
- 22nd May 2008, 16:39
A 40 pin PIC that is 16F877 compatible will be very flexible. There are 18F's that are pin compatible.

For features, it is all up to what you want out of it. You can read up on many. I've used the MELabs X1, and been happy with it. They also have one that is telephone based, but if you aren't working with phone equipment, that's not of much use. The mikroe boards have numerous features, with add-on modules.

DaveC3
- 22nd May 2008, 23:17
I would suggest the 18F4550. It can be programmed via MicroChip's free USB Boot-loader (after the boot-loader hex code is loaded). After that it has plenty of inputs and outputs, all the special functions like I2C, Serial, 13 A/D etc.

The student's applications can be from a very simple blink program to almost any other application you can think of. Being a USB device it can also be used fro PC to PIC communications, joysticks, game controllers, special USB keyboards, displays etc.

The USB Boot-loader makes it easy and fast to test code.

Thanks

Dave

mister_e
- 23rd May 2008, 00:38
Of course not the F877(a) as it's almost obsolete anyways. I would suggest the 16F887 or PIC18F4520... but that doesn't cover the USB. So go for the 18F2550 or 18F4550. As long as you can deal with the fact that the dedicated USB pins can't be used as standard i/o (mostly only as Input), then you should be able to cover almost everything you have on your current list...except the USB slave... where you need an interface in between OR go for a bigger PIC with USB OTG... but it won't work with PBP... nothing is perfect :D

PICKIT2 will be perfect... and now it has the Logic Analyser utility, that could be handy.

A bit pointless to go for the Bootloader... at least student won't learn how to set config fuses and how to program them in-circuit and how to design something for ICSP support. Pickit2 is a fast programmer, sure it's faster than most Bootloader.

Is there a board with everything in your list? Probably not 100%. Have a look at MikroElektronika EasyPic 5... and their expansion modules. And probably that one...
http://www.picbasic.co.uk/forum/showthread.php?t=8817

You could still design your own 'main board' on which you just plug some plug-in modules.

HTH

PJALM
- 23rd May 2008, 05:40
Thanks Mister_E

The whole point of the class is to learn PCB fabrication and layout so designing their own board is what we intend to do. the 18F4520 is nice but small. I was thinking something around the 80 to 100 pin count. Probably whatever the biggest one the PicBasic supports if not then we may just use mikroBasic instead. All those pre made boards are nice but doesn't help them learn the whole PCB fabrication process. The board they make is most likely going to be 4 to 8 layers so i want to stuff it with as much as we can.

mister_e
- 23rd May 2008, 05:46
Well you could go for the 18F97J60. This is the biggest PBP can support, and i think it's the bigest 18F of Microchip 'till now.

I'm waiting for few samples of it. BIG PIC indeed, small pins though, maybe not that easy to solder.

18F8722 is still 'interesting' for a 80 pins, but not that much features.

PJALM
- 24th May 2008, 04:01
Thanks again

That PIC sounds perfect for what we want. Soldering that part shouldn't be a problem for we have the latest in SMD soldering equipment.