Hi Seb, I didn't follow deeply the subject, I will answer punctual below:
On 8/28/09, Sebastien Lelong <[email protected]> wrote: > > Hi guys, hi Richard, > > Since last try to build Jaluino v1.0 ( > http://jallib.blogspot.com/2009/08/building-jaluino-v10.html), I've been > thinking a lot about what could be improved and added. Here's a list of > point I think it can be nice to have, though I understand not all may be > doable in a homebrew version. Anyway they will be here as a reminder... > > - I²C: current version isn't I²C enabled. That would be really great to > have this. There are different options I can think, depending on how the PCB > can get complex: > > 1. Two resistors, with jumpers to select whether you want to i2c enabled > or not, and a connector (see Joep suggestion: > http://groups.google.com/group/jallib/msg/2042aeffaba02b33?hl=en). SDA/SCL > are exposed through shield connectors. Depends what are you thinking. USB PIC's are not pin to pin compatible with old 5V PICs. 3.3V PICs are almost compatible with old 5V PICs with minor differences (+2.5V internal supply pin). If you need an universal device, focuse on what PIC is better/cheaper for you. I do not understand why don't you keep Ithe 2C enabled permanently and check if something is received. If not, disable it automatically (if that is usefull for something...) 2. Two resistors, with jumpers to select whether you want to i2c enabled > or not. No connector, SDA/SCL still usable via connectors. > > 3. Two resistors. Either you solder them, either not, whether you want > I2C or not (but switching master/slave will be a pain...) > > 4. Last option, two resistors to solder or not, and the i2c connector. > > - Being able to use 3.3V power source. I know it adds another part and > use lots of precious space, but it might possible since there are some space > at the bottom. Should 3.3V be produced by jack power, USB or serial source, > or just jack and USB ? You can use a cheap 3.3V LDO as BA033 from Rohm, cheap and stable. Input voltage either USB or jack power. - last point, and the most important IMO, increase the space between upper > and bottom shield connectors. Using your measurement file, this is "16 pitch > = 40.64 mm" (note I measure ~40.18mm, am I wrong ?). I think it's way too > narrow, because you can't even put a mini-breadboard between them. As you > said in a previous mail, if we want to have this intermediate shield, > distance has to be different from Arduino (or the shield will be hard to > create). What do you think about a distance a little bit bigger than > Arduino. For Arduino, I measure ~49mm, what about something like 55mm ? > Power connector on the left can remain uncentered IMO. > > I wish I could help with the PCB, like moving these connectors, but I don't > have Orcad and don't know how to use it (I may give a try with the demo > version if it's not too limited). I strongly suggest to move on SMD design (cheapper/smaller/proffesional). When you'll have near 50 (as I'm going to...) you'll go back to DIP because of glasses... Cheers, > Seb > -- > Sébastien Lelong > http://www.sirloon.net > http://sirbot.org > > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "jallib" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/jallib?hl=en -~----------~----~----~----~------~----~------~--~---
