On 24/08/2011 18:28, Steven King wrote: > On Wednesday 24 August 2011 06:06:52 Angelo Dureghello wrote: >> Hi, >> >> i did a step forward, genromfs was old: >> >> http://mailman.uclinux.org/pipermail/uclinux-dev/2011-February/002993.html >> >> Now i have i2c-0 device created. >> >> i2c-core: driver [rtc-ds1307] registered >> i2c /dev entries driver >> i2c-core: driver [dev_driver] registered >> TCP cubic registered >> NET: Registered protocol family 17 >> drivers/rtc/hctosys.c: unable to open rtc device (rtc0) >> >> I also created rtc0, i don't understand why it cannot be open. > > Hi Angelo, > > Could you give some details about your hardware setup? Is the 5307 a > Freescale 5307evb or a custom board? And is the ds1307 built on the board or > external? And could you post your full .config? > > The first thing to check is if the i2c bus has the proper pullups. Some > evb's > have them built in, some have jumpers to enable or disable them and some dont > have them at all. Also, IIRC, the ds1307 is 5 volt only, so if your cpu is > running at 3.3v or 1.8v, you'll need some sort of level shifter on the i2c > signals.
Hi Steven, Great, bingo. The board is a custom board designed by me, and a good reason why the ds1307 don't work is that has been powered at 3.3V. I will try, just for test to add some diodes to go almost over > 4.5, and let you know. Pullups are good, as specified in the datasheet. Once it work there must be a kind of autodetection/probe, right ? Regards, angelo _______________________________________________ uClinux-dev mailing list uClinux-dev@uclinux.org http://mailman.uclinux.org/mailman/listinfo/uclinux-dev This message was resent by uclinux-dev@uclinux.org To unsubscribe see: http://mailman.uclinux.org/mailman/options/uclinux-dev
