Hi, Please tell me about correct circuitry to use boot pins as input, I use Beaglbone Black and want to use these pins, especially eQep counter pins P8-33,35,41,42 that match to SYS_BOOT 4,5,12,13.
In SRM (ver A6) p104 it says, "If you plan to use any of these signals, then on power up, these pins should not be driven." Which of below is correct circuitry? A) Attach pins to ground until SYS_RESETn goes high. B) Keep pins floated until SYS_RESETn goes high. A is easier, because it can be done by switching 1 relay pulling all pins to ground. For B, I need plenty relays. Thanks, Tohru 2013年4月12日金曜日 4時20分23秒 UTC+9 DarkHelmet: > > You can absolutely use them for other usages, once the value has been > latched at boot they can be re purposed It may be necessary > to strengthen the pull up/down on those lines with external resistors > though. I've encountered an issue where my TTL inputs were pulling the > lines low at boot while the CPU latched the config, preventing it to boot > from the correct configuration. Resistors of ~50k seem to do the trick. > > On Friday, April 5, 2013 6:04:18 AM UTC-4, [email protected] wrote: >> >> Hi, >> >> I've a beaglebone with the XAM3359Z0Z, >> >> >> I discovered that there is 19 pins dedicated to the boot configuration. >> The documentation said that depending of the position of the switch, The >> beaglebone will boot with the sd card, uart, ..... . >> ( >> http://processors.wiki.ti.com/index.php/AM335X_StarterWare_Booting_And_Flashing#Boot_Modes >> ) >> >> >> I wanted to know if it is possible to use these pins for an another >> usage? How ? I don't need an another boot mode, the default one is enough >> for me. >> >> >> >> Thank you in advance for your help, >> > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/groups/opt_out.
