Date: Fri, 20 Sep 2024 22:54:30 +0100 From: Warner Losh <imp@bsdimp.com> To: "Bjoern A. Zeeb" <bzeeb-lists@lists.zabbadoz.net> Cc: "freebsd-hackers@freebsd.org" <hackers@freebsd.org> Subject: Re: gpio pins -> tty/cua device Message-ID: <CANCZdfr70CsutBZ_eUP1dRK_6XFgjpZCKZaWf6LFMF8m1iwkRA@mail.gmail.com> In-Reply-To: <pp20o9o7-7937-o09n-or3n-4rp409q13q46@yvfgf.mnoonqbm.arg> References: <pp20o9o7-7937-o09n-or3n-4rp409q13q46@yvfgf.mnoonqbm.arg>
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--0000000000001999460622941687 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Fri, Sep 20, 2024, 10:49=E2=80=AFPM Bjoern A. Zeeb < bzeeb-lists@lists.zabbadoz.net> wrote: > Hi. > > I have one/two GPIO pins for RX/TX (possibly on two controllers) which > on the other end have a serial console which I would love to read/wwrite > to. > > Do we have any glue which takes two GPIO pins and present them as tty/cua > device? > No. We don't do serial emulation through software. You need high precision timers paired with it to even start. And input bytes are way harder to get right. Likely need a dedicated thread for any decent data rates. What speed were you hoping for? Warner /bz > > -- > Bjoern A. Zeeb r15:7 > > --0000000000001999460622941687 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable <div dir=3D"auto"><div><br><br><div class=3D"gmail_quote"><div dir=3D"ltr" = class=3D"gmail_attr">On Fri, Sep 20, 2024, 10:49=E2=80=AFPM Bjoern A. Zeeb = <<a href=3D"mailto:bzeeb-lists@lists.zabbadoz.net">bzeeb-lists@lists.zab= badoz.net</a>> wrote:<br></div><blockquote class=3D"gmail_quote" style= =3D"margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Hi.<br> <br> I have one/two GPIO pins for RX/TX (possibly on two controllers) which<br> on the other end have a serial console which I would love to read/wwrite to= .<br> <br> Do we have any glue which takes two GPIO pins and present them as tty/cua d= evice?<br></blockquote></div></div><div dir=3D"auto"><br></div><div dir=3D"= auto">No. We don't do serial emulation through software. You need high = precision timers paired with it to even start. And input bytes are way hard= er to get right. Likely need a dedicated thread for any decent data rates. = What speed were you hoping for?</div><div dir=3D"auto"><br></div><div dir= =3D"auto">Warner</div><div dir=3D"auto"><br></div><div dir=3D"auto"><div cl= ass=3D"gmail_quote"><blockquote class=3D"gmail_quote" style=3D"margin:0 0 0= .8ex;border-left:1px #ccc solid;padding-left:1ex"> /bz<br> <br> -- <br> Bjoern A. Zeeb=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2= =A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 = =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0r15:7<br> <br> </blockquote></div></div></div> --0000000000001999460622941687--
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