I designed one for the MEGA8U with heart beat LED, reset button, USB and a ICSP socket.  Just to allow me to place it on a breadboard program the bootloader and have a play with it really.  I ordered 10 of them including postage for £10 ($15 ish).  I found a resonator on Eagle which was smaller than a normal crystal and with it being a resonator rather than a crystal and caps it saved 2 components.

All the info in relation to the caps to use with crystals says 22pF and this is what I use but I am putting together a board the size of a 40pin DIL but containing USB port, ICSP port crystal, heart beat LED etc etc for breadboarding.

In order to get the component count down and keep the device within size constraints I have been looking for an alternative to the typical crystal and caps way of doing things and found few resonators which run at the right speed and are SMD so perfect BUT they have different capacitor values.

What is the range of values that will work correctly?

Can anyone point me at suitable SMD resonators for 16MHz & 8MHz operation.

Thanks.

Well after struggling along I've found another.

1280/2560



This is the one I really wanted

Thanks.  My board design is taking shape.  The alternative method seem soooooo much more complicated !

Whilst building devices based on the actual IC rather than a board it would be helpful to have a table of Arduino digital pin number to leg number etc I have tried to find such a thing but as yet no luck.  Does anybody know of such a thing?  A table for various ICs would be best

My latest device is going to have a 1280 at the centre.  I have finished the FTDI part, the power supply etc and added the other components but I'm now left with about 80 legs to work out

Help would be appreciated.

Something like this, which is for the 328 would be good.

Is there any issue using the MEGA 1280 IC with an FTDI chip?  Obviously 8U2 is being used on their reference board but can I just go down the FTDI route as with previous ICs?

Thanks, that worked.

I have tried but it's not working....

This is the include command:

#include <MMCdefinitions.h>

and I have tried to following it the sketch directory...

Program.ino
MCCdefinitions.h

or

Program.ino
MCCdefinitions with MCCdefinitions.h inside

or

Program.ino
library with MCCdefinitions.h inside

or


Program.ino
library with folder MCCdefinitions inside with MCCdefinitions.h inside

Thankyou

I want to create a working library that changes as I program it before it replaces the original library but I can't work out how to make the program refer to a library that is in the program folder.  This also allows it to be relative and so that I can just zip the whole folder and send it as it is to the other person developing the hardware with me without having to get the library(s) as well.

It's got to be a simple thing but it's stumped me

I ended up having to buy an AVR ISP MK2 and then you have to connect using AVR Studio 5 and begin communications at the absolute slowest speed the program allows.  Once communicating you can set the flags etc and push the speed back up again, I normally use 1MHz just to upload the boot loader.

No good in series, in the end I had to use 3 X ( 3 resistors + 2 transistors) which meant that I had to switch to SMD parts and re lay the moveable components on the board so everything fit.

Pins 1 & 20 are normally ground on a type B GLCD I didn't realise that those pins were in the ground plane.

It looks ok from a cursory glance.  Is it aiming to be used for something in particular or as the basis for something else.

Hello all,

In my zeal to use the 1284P with a "type B" GLCD (JHD12864E), I have made this board.

Can anyone please review this and comment / suggest changes?

However, please note, because of size constraints, the PCB can be only 4"(W) x 3"(H).

Thanks,
Madhu.

Your LCD connector doesn't appear to be grounded.

Could you hook the pin to a pair of transistors?

That was plan B

I was hoping for an alternative if possible as with that plan it's quite a number of extra components as I'm driving the 3 LEDs and 3 opto-couples from 3 legs.