From: R. P. M. <log...@gm...> - 2009-12-21 14:54:21
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Things like the wireless use their own signals that do not interfere with the signals available on the connectors. However, perhaps you want to use something like, say, a UART. The wireless also uses a UART and it is possible that if you try to use the same UART (but on the alternate pins) that the wireless will no longer function. Is that what you mean? On 12/21/09, comrex <har...@gm...> wrote: > > Sorry to beat a dead horse here, but to give you an example why that's not > enough info: > > I want to design my motherboard with a DMA-capable interface to the > expansion bus. OK, so the hardware pinout gives me the basic signals, but > not the irq, dma request line, wait pin etc. These are found on alternate > functions of other pins that happen to be available on the connector. > > But which ones do I choose? I have to guess because Gumstix has not laid out > exactly what they use for things like their wireless interface, boot prom, > etc. > > This is just an example. If I want to utilize alternate pins for SPI, McBSP, > I2C etc I'm in the same boat. > > Not they they don't have their own support issues, but a competing product > from Compulab has a real hardware user's guide with detailed explanation of > what's connected where on their boards. > > http://www.compulab.co.il/t3530/html/t3530-cm-datasheet.htm > > > Dave Hylands wrote: >> >> Hi, >> >> On Sun, Dec 20, 2009 at 6:40 PM, comrex <har...@gm...> wrote: >>> >>> NTN thanks for the response. >>> >>> Well that's a start but it doesn't settle the matter. Most of these pins >>> have different functions in alternate modes. If, for example, I was >>> interested in using a UART or McBSP not found in the mode 0 settings of >>> these pins. I have no way to know whether these ports are in use already >>> on >>> other pins. >>> >>> Essentially, instead of letting us know what's not used, Gumstix should >>> be >>> telling us what ports *are* in use. >> >> The overo motherboard itself will probably only use the essential pins >> to make it run. i.e. address and data lines, and similar. >> >> As a general rule, all of the pins which are brought out to the >> connectors are available. Many of them come directly from the >> processor, so you can read about the functionality by looking at the >> processor data sheet. >> >> Which signals are available once a daughtercard gets involved depends >> on the functionality provided by the daughtercard, and all of the >> schematics for the daughtercards are available. >> >> -- >> Dave Hylands >> Shuswap, BC, Canada >> http://www.DaveHylands.com/ >> >> ------------------------------------------------------------------------------ >> This SF.Net email is sponsored by the Verizon Developer Community >> Take advantage of Verizon's best-in-class app development support >> A streamlined, 14 day to market process makes app distribution fast and >> easy >> Join now and get one step closer to millions of Verizon customers >> http://p.sf.net/sfu/verizon-dev2dev >> _______________________________________________ >> gumstix-users mailing list >> gum...@li... >> https://lists.sourceforge.net/lists/listinfo/gumstix-users >> >> > > -- > View this message in context: > http://old.nabble.com/Avoiding-conflicts-on-Overo-connectors-tp26856701p26874606.html > Sent from the Gumstix mailing list archive at Nabble.com. > > > ------------------------------------------------------------------------------ > This SF.Net email is sponsored by the Verizon Developer Community > Take advantage of Verizon's best-in-class app development support > A streamlined, 14 day to market process makes app distribution fast and easy > Join now and get one step closer to millions of Verizon customers > http://p.sf.net/sfu/verizon-dev2dev > _______________________________________________ > gumstix-users mailing list > gum...@li... > https://lists.sourceforge.net/lists/listinfo/gumstix-users > |