Date: Wed, 15 May 2013 09:46:01 -0400 From: Warner Losh <imp@bsdimp.com> To: Tom Everett <tom@khubla.com> Cc: Aleksandr Rybalko <ray@freebsd.org>, "freebsd-arm@freebsd.org" <freebsd-arm@freebsd.org> Subject: Re: RS-232 driver for GPIO Message-ID: <C37D5616-255B-45C5-A2E3-1257A73773CF@bsdimp.com> In-Reply-To: <CAB3ij4DrNMFD%2BKm0Cf=O_1TonXpYGnX67jfAVE0=8PbH=9OywQ@mail.gmail.com> References: <CAB3ij4AzL8B6nS1kFa%2BgjmAVEOE8qO7UwPv_vBzRPn1sUNYuDQ@mail.gmail.com> <CAJ-Vmo=ZzAOyy9hWzMDw7bt9=nxsEzyAJnScgL-3NFfzcf7RXA@mail.gmail.com> <20130514192448.7b48e095.ray@freebsd.org> <CAB3ij4DLEBe_R1ydVJ0T-V0-ufizMHERNnPuzO_DY8iOE=1kSQ@mail.gmail.com> <20130515021751.8848a996.ray@freebsd.org> <CAB3ij4Ctq9j0svwqeUJk32Ugy6NJ1W7PJ9rrTue%2BtyDnky5g_Q@mail.gmail.com> <20130515122955.4387631e9969ae460f6500c7@freebsd.org> <CAB3ij4DrNMFD%2BKm0Cf=O_1TonXpYGnX67jfAVE0=8PbH=9OywQ@mail.gmail.com>
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On May 15, 2013, at 9:40 AM, Tom Everett wrote: > ok, just one further question. It was basically guess work that = enabled me > to decypher that /dev/ttyu0 (sio0) was bound to uart0. I presume = there > must be some simple way from the command line to query the OS and find = out > which hardware devices are bound to which /dev/ entries? The unit numbers generally match the alias names in the FDT. However, we don't note what the names for the nodes we're attaching to = on FDT systems. We really should, but we don't... Warner > On Wed, May 15, 2013 at 3:29 AM, Aleksandr Rybalko <ray@freebsd.org> = wrote: >=20 >> On Tue, 14 May 2013 20:24:42 -0600 >> Tom Everett <tom@khubla.com> wrote: >>=20 >>> Did you mean 14 &15, or 14 & 16? >> Yeah, right. >>=20 >>=20 >>> ok so given this, I've done some reading. I'm by no means a FreeBSD >>> expert, so forgive me if I'm completely wrong. I see this in the = FDT: >>>=20 >>> /* UART0 */ >>> pins_uart0_a: uart0_a { >>> broadcom,pins =3D <14>, <15>; >>> broadcom,function =3D "ALT0"; >>> }; >>=20 >> If you satisfied by single UART, you no need change that. >>=20 >>=20 >>>=20 >>>=20 >>> and this: >>>=20 >>> chosen { >>> bootargs =3D ""; /* Set by VideoCore = */ >>> stdin =3D "uart0"; >>> stdout =3D "uart0"; >>> }; >>>=20 >>=20 >> But that stdin and stdout direct kernel console messages to air by = your >> xbee :) >> So you need comment it or set different in/out device. >>=20 >>=20 >>>=20 >>> So I interpret that to mean that uart0 is bound to pins 14, 15, and >>> furthermore that the serial device bound to uart0 is bound to stdin = and >>> stdout. In my /dev/ I see: >>>=20 >>> crw------- 1 root wheel 0x1f Apr 27 13:42 ttyu0 >>> crw------- 1 root wheel 0x20 Apr 27 21:42 ttyu0.init >>> crw------- 1 root wheel 0x21 Apr 27 21:42 ttyu0.lock >>> crw-rw---- 1 uucp dialer 0x22 Apr 27 21:42 cuau0 >>> crw-rw---- 1 uucp dialer 0x23 Apr 27 21:42 cuau0.init >>> crw-rw---- 1 uucp dialer 0x24 Apr 27 21:42 cuau0.lock >>>=20 >>> So, that is telling me that sio0 is bound to uart0, which is a = serial >>> console? >>=20 >> Yep. >>=20 >>>=20 >>> If so, that means that I could use pins 14 & 15 for rs-232, but I = would >>> have to chose b/t using those pins to talk to another device (xbee), = or a >>> serial console? >>=20 >> if you will disconnect serial console you will have to choose between >> control over network (SSH/telnet/etc) or graphic console (Display = with >> HDMI + USB keyboard). >>=20 >>>=20 >>>=20 >>>=20 >>>=20 >>>=20 >>> On Tue, May 14, 2013 at 5:17 PM, Aleksandr Rybalko <ray@freebsd.org> >> wrote: >>>=20 >>>> On Tue, 14 May 2013 12:20:08 -0600 >>>> Tom Everett <tom@khubla.com> wrote: >>>>=20 >>>>> ok so the FDT definition would have to be added here? >>>>>=20 >>>>>=20 >>>>=20 >> = http://svnweb.freebsd.org/base/head/sys/boot/fdt/dts/bcm2835-rpi-b.dts?vie= w=3Dmarkup >>>>>=20 >>>>=20 >>>> Yeah, right. >>>>=20 >>>> But I have bad news. Both UARTs can be connected to pairs(tx+rx) = 14+16, >>>> 32+33, 40+41 and both UARTs can be connected to any of this pins. >>>> But only 14, 16 and 40(PWM0) wired to ext.pin. >>>>=20 >>>>>=20 >>>>>=20 >>>>> On Tue, May 14, 2013 at 10:24 AM, Aleksandr Rybalko = <ray@freebsd.org >>>=20 >>>>> wrote: >>>>>=20 >>>>>> On Tue, 14 May 2013 09:06:44 -0700 >>>>>> Adrian Chadd <adrian@freebsd.org> wrote: >>>>>>=20 >>>>>>> ... the r-pi actually has an RS232 port exposed via GPIO. It's >>>>>>> only 3.3v but it's there. >>>>>>>=20 >>>>>>> Someone just needs to write up an SIO driver for it and then put >>>>>>> the GPIO pins in question into RS232 "mode". >>>>>>=20 >>>>>> we have it already :) (console works on uart) >>>>>> only FDT definition is required. >>>>>> And maybe some fixes for boudrate setting and/or format setup >>>>>> (bits/parity/stop bits/etc) >>>>>>=20 >>>>>>>=20 >>>>>>> Yay multi-function GPIO pins! >>>>>>>=20 >>>>>>>=20 >>>>>>>=20 >>>>>>> adrian >>>>>>>=20 >>>>>>>=20 >>>>>>> On 14 May 2013 08:58, Tom Everett <tom@khubla.com> wrote: >>>>>>>> Good morning ARM mailing list. >>>>>>>>=20 >>>>>>>> I've been running FreeBSD on my Pi, and I've now got two XBee >>>>>>>> Pros which I hope to connect. XBee's communicate over RS-232. >>>>>>>>=20 >>>>>>>> https://www.sparkfun.com/products/8742 >>>>>>>>=20 >>>>>>>> I see from the source tree that it was possible to attach the >>>>>>>> iic driver to GPIO pins in software: >>>>>>>>=20 >>>>>>>>=20 >>>> = http://svnweb.freebsd.org/base/head/sys/dev/gpio/gpioiic.c?view=3Dmarkup >>>>>>>>=20 >>>>>>>> I'm wondering, it is possible to connect the FreeBSD serial >>>>>>>> driver for RS-2332 to GPIO in a similar way to how iic was >>>>>>>> connected? >>>>>>>>=20 >>>>>>>>=20 >>>>>>>>=20 >>>>>>>> -- >>>>>>>> A better world shall emerge based on faith and understanding - >>>>>>>> Douglas MacArthur >>>>>>>> _______________________________________________ >>>>>>>> freebsd-arm@freebsd.org mailing list >>>>>>>> http://lists.freebsd.org/mailman/listinfo/freebsd-arm >>>>>>>> To unsubscribe, send any mail to >>>>>>>> "freebsd-arm-unsubscribe@freebsd.org" >>>>>>> _______________________________________________ >>>>>>> freebsd-arm@freebsd.org mailing list >>>>>>> http://lists.freebsd.org/mailman/listinfo/freebsd-arm >>>>>>> To unsubscribe, send any mail to >>>>>>> "freebsd-arm-unsubscribe@freebsd.org" >>>>>>=20 >>>>>>=20 >>>>>> -- >>>>>> Aleksandr Rybalko <ray@freebsd.org> >>>>>>=20 >>>>>=20 >>>>>=20 >>>>>=20 >>>>> -- >>>>> A better world shall emerge based on faith and understanding - >>>>> Douglas MacArthur >>>>=20 >>>>=20 >>>> -- >>>> Aleksandr Rybalko <ray@freebsd.org> >>>>=20 >>>=20 >>>=20 >>>=20 >>> -- >>> A better world shall emerge based on faith and understanding - = Douglas >>> MacArthur >>=20 >> Good luck! And let us know how things is going :) >>=20 >> WBW >> -- >> Aleksandr Rybalko <ray@freebsd.org> >>=20 >=20 >=20 >=20 > --=20 > A better world shall emerge based on faith and understanding - = Douglas > MacArthur > _______________________________________________ > freebsd-arm@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-arm > To unsubscribe, send any mail to "freebsd-arm-unsubscribe@freebsd.org"
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