On Thu, 1 May 2008 08:31:16 +0800 Carsten Haitzler (The Rasterman) <[EMAIL PROTECTED]> babbled:
forgot to say.. don't like 2 plugs on the outside though... maybe we can hide one under the back cover or something? (really come on -how often will u want power from charging AND need to run a usb device as a host for a long period of time? if you have power to charge.. u are likely @ home or office... and u can do things on your laptop or desktop...). > On Wed, 30 Apr 2008 19:28:21 +0200 Joachim Steiger <[EMAIL PROTECTED]> > babbled: > > > sorry for jumping into this thread so late... > > > > we are at the point of considering having 2! external accessible usb > > connectors for reasons of not wanting to sacrifice charging while using > > usb client OR host as well as providing power to usb host if wanted as > > well as having a internal debugboard. > > > > this all got me thinking.. especially all this nonsense of 'usb > > certifications' (if you ask me, do whats reasonable and helps people to > > use stuff in the real world, and ignore all the nonsense parts) > > > > - i really like my mini-usb. (for mechanical, practical and spread in > > the real world) > > - i have till now not seen a single micro-usb wallwart charger or carkit > > in the real world (nor a device which uses that connector at all). > > - the N8xx series is the only device i know i were near which does OTG > > as far as i know. > > > > thus my questions: > > - why not put a mini-usb-b like we have now onto the device? > > * do charging and client mode there. no host > > * be usb compliant when it comes to 100/500mA with usb enum > > * detect and use chargers with either id-resistor of known value and > > thus current > > * AND be able to detect usb charging spec (which is just nailed down > > what was in use before and now) by checking short on D+ and D- > > (eventually you can switch them to gpio and wiggle one and watch the other?) > > = > compliant with all carkits and wallwarts which i know of. > > means 'it will work' (and charge) in any case i can imagine and not > > endanger any fuses on mainboards ;) > > > > to the usb-host part: > > we are talking about a second connector there. > > - why not make it usb-(mini)-A ? > > * i would rather like A due to the more widespread of cables and > > devices, but its propably too big > > * provide 100 or 500mA there. > > * put a single 2-positions switch below the battery flap to switch this > > whole port to jtag. > > = > would enable directly plugging loads of usb client stuff. > > - also makes the schematic much easier. less complicated cornercases. > > - the _only_ point where somebody needs a nonstandard cable is when > > using jtag ((mini)-A to A). and it is only a cable, no electronics. > > => ALL other usecases are available without any non-usb standard cables, > > devices, pinouts or whatever. like total compliance with everything of > > usb that makes sense AND keeping our beloved 'can do all' features while > > still knowing what people will plug together when plugs fit and make it > > work. > > > > additional thoughts: > > * put both connectors to one side of the case (enable docking both with > > fixed plugs in some kind of cradle > > * leave enough space between for silly stuff which is wider than a > > simple connector. > > > > please let me know what you think > > i agree on all - mini not micro usb, and the switch sounds nice (though from > an ID point of view sean is mentioning having the back held in by screws so > changing that switch may be a little hard, but then again... how often will an > end user really need jtag?). > > i definitely think we need to have the usb connector at the bottom of the case > - not the side. docking/cradles really would demand this. > > > > > -- > > > > Joachim Steiger > > Central Services > > > > _______________________________________________ > > hardware mailing list > > [email protected] > > http://lists.openmoko.org/mailman/listinfo/hardware > > > -- > Carsten Haitzler (The Rasterman) <[EMAIL PROTECTED]> > > _______________________________________________ > hardware mailing list > [email protected] > http://lists.openmoko.org/mailman/listinfo/hardware -- Carsten Haitzler (The Rasterman) <[EMAIL PROTECTED]> _______________________________________________ hardware mailing list [email protected] http://lists.openmoko.org/mailman/listinfo/hardware
