From owner-freebsd-arm@freebsd.org Fri Nov 25 14:07:34 2016 Return-Path: Delivered-To: freebsd-arm@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id AC9DFC545BF for ; Fri, 25 Nov 2016 14:07:34 +0000 (UTC) (envelope-from markmi@dsl-only.net) Received: from asp.reflexion.net (outbound-mail-210-29.reflexion.net [208.70.210.29]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 5B2F0A86 for ; Fri, 25 Nov 2016 14:07:33 +0000 (UTC) (envelope-from markmi@dsl-only.net) Received: (qmail 24269 invoked from network); 25 Nov 2016 14:07:12 -0000 Received: from unknown (HELO mail-cs-02.app.dca.reflexion.local) (10.81.19.2) by 0 (rfx-qmail) with SMTP; 25 Nov 2016 14:07:12 -0000 Received: by mail-cs-02.app.dca.reflexion.local (Reflexion email security v8.20.0) with SMTP; Fri, 25 Nov 2016 09:07:33 -0500 (EST) Received: (qmail 24881 invoked from network); 25 Nov 2016 14:07:33 -0000 Received: from unknown (HELO iron2.pdx.net) (69.64.224.71) by 0 (rfx-qmail) with (AES256-SHA encrypted) SMTP; 25 Nov 2016 14:07:33 -0000 Received: from [192.168.1.106] (c-76-115-7-162.hsd1.or.comcast.net [76.115.7.162]) by iron2.pdx.net (Postfix) with ESMTPSA id 56FA5EC907A; Fri, 25 Nov 2016 06:07:26 -0800 (PST) Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 10.1 \(3251\)) Subject: Re: Can't get 11.0-RELEASE to boot on Banana PI M3 From: Mark Millard In-Reply-To: <20161125105751.8F15A406061@ip-64-139-1-69.sjc.megapath.net> Date: Fri, 25 Nov 2016 06:07:25 -0800 Cc: freebsd-arm Content-Transfer-Encoding: quoted-printable Message-Id: <9211EF99-1E69-4BC0-91CC-DF6604FE8655@dsl-only.net> References: <20161125105751.8F15A406061@ip-64-139-1-69.sjc.megapath.net> To: Michael Sperber X-Mailer: Apple Mail (2.3251) X-BeenThere: freebsd-arm@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: "Porting FreeBSD to ARM processors." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 25 Nov 2016 14:07:34 -0000 On 2016-Nov-25, at 2:57 AM, Hal Murray = wrote: > sperber at deinprogramm.de said: >> Ah, thanks ... but that's not standard RS232, right? (BPI homepages = says >> "TTL".) If it isn't, what kind of hardware connects to that?=20 >=20 > The normal setup for RS232 is that the transmit and receive signals = come out=20 > of a big chip (SOC, or PCI UART, or USB UART, or ...) and then go = through a=20 > level converter which is typically a MAX-232 or one of many clones or=20= > variants. The "TTL" is telling you that it doesn't have that level = converter=20 > chip. >=20 > You can either add a level converter chip and then plug it into a real = RS-232=20 > port, or find some setup that also doesn't have the level converter = and=20 > speaks TTL levels. Adafruit and probably many others sell a USB UART = without=20 > the level converter for applications like this. > https://www.adafruit.com/product/954 I use one of those from adafruit for a BPi-M3, a RPI2B V1.1, or a = Pine64. > Sometimes, TTL means 3V CMOS levels and 5V from real TTL/CMOS will fry = your=20 > expensive chip. Best to check carefully. The above part says 3V. It = also=20 > has an extra power wire that you get to ignore. =3D=3D=3D Mark Millard markmi at dsl-only.net