I am drawing a general purpose shield for the DUE/Mega using ExpressPCB. Eagle files are available for the boards as well as for several shields but I do not have Eagle. Can someone please verify that all of the headers are on .1" centers with two exceptions. the ICSP header seems to be off grid. the header for digital pins 8-13 and Aref etc is off by .05" its the adjacent pins on this and the header with digital pins 0-7 are .15" apart instead of .2" as with the case with all other adjacent headers. the SPI header is on .1" grid
because i am too cheap to buy Eagle and too lazy to learn to use it. i am making the general purpose shield but will only have it made once i add additional circuits. i need to cram a lot on (a POR chip, quadrature decoder, SD card socket in an accessible position, screw terminals and an auxiliary microcontroller) and don't want to do a lot of point to point wiring. i have some dev shields on the way and will use these for prototyping but once i figure out what i need, i will copy the circuit to the general purpose layout.
the project i am working on needs to have a lot of stuff between the DUE and a TFT shield. i can probably fit it all on both sides of the dev shield but don't want to wire another board once the proto is working.
I believe your pin spacings are correct, although I haven't looked at the ICSP header.
There is a free version of Eagle which I use to examine the Arduino reference files.
For creating PCBs, I use Kicad. There are some Arduino footprints already available for Kicad. I can provide some Due footprints for Kicad if you like.
any help in this regard would be appreciated. i would like to print out bout layouts to a large scale and see if they register. my printer seems to not be totally accurate so i can not print out board sized registration check sheets. i will check out Kicad. please send me the layouts for DUE or tell me where to get them. also any links for kicad would be appreciated in case i can't find them. you can e-mail the files to spencer@spencerserolls.com
See if Kicad will import the Mega board file - strip out the parts you don't want and go from there.
If it won't - then you have a tougher job ahead.
I started with the Arduino files here Arduino Shield Modules for KiCad V3 by nicholasclewis - Thingiverse by nicholasclewis.
My adapted versions for Due on my github GitHub - bobc/bobc_hardware: Various hardware projects. All the Kicad footprints I use are under bobc_hardware/KiCAD_Libraries at master · bobc/bobc_hardware · GitHub, in the RMC.* files, and files from nicholasclewis. To use symbols or footprints you need to explicitly add them to you Kicad projects.
The Due shield I have been working on is under RAMPS-FD (RAMPS-FD - RepRap).
If you find anything missing or broken, please let me know, some things get overlooked or reorganised. For queries on Kicad, the group http://tech.groups.yahoo.com/group/kicad-users/ is usually helpful. The site at http://www.kicad-pcb.org/display/KICAD/KiCad+EDA+Software+Suite also has lots of useful info and downloads.
Where can I buy one of the Mega Screw Shield? Thanks!
FYI, digital pins 0-7 are 0.16" away from the next group, not 0.15". I've heard that 0.15" works OK, but if you want it to be exactly right...
Daytrader,
I ship the megascrewshield kit worldwide.
$35 for the kit plus mailing cost, generally ~$5 in the US, international I try to find less expensive method than USPS flat rate ship anywhere in the world, currently $24!
http://ircalc.usps.com/MailServices.aspx?country=10150&m=13&p=0&o=1&mt=20
Seems to depend on who's manning the counter; smaller padded envelopes are less sometimes.
Robert