From owner-freebsd-arm@freebsd.org Wed Nov 13 22:11:03 2019 Return-Path: Delivered-To: freebsd-arm@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 9F4241BD635 for ; Wed, 13 Nov 2019 22:11:03 +0000 (UTC) (envelope-from ticso@cicely7.cicely.de) Received: from raven.bwct.de (raven.bwct.de [195.149.99.3]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "raven.bwct.de", Issuer "raven.bwct.de" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 47CzMq2YC1z4MnR; Wed, 13 Nov 2019 22:11:02 +0000 (UTC) (envelope-from ticso@cicely7.cicely.de) Received: from mail.cicely.de ([10.1.1.37]) by raven.bwct.de (8.15.2/8.15.2) with ESMTPS id xADMBnYY051258 (version=TLSv1 cipher=DHE-RSA-AES256-SHA bits=256 verify=FAIL); Wed, 13 Nov 2019 23:11:50 +0100 (CET) (envelope-from ticso@cicely7.cicely.de) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=cicely.de; s=default; t=1573683110; bh=oVG4/T0er7Nh1jxilotyteWy+ljMoDGt7eaHyIdLPdA=; h=Date:From:To:Cc:Subject:Reply-To:References:In-Reply-To; b=Wps74gfmoOIKUjQvbZS7z5wmduuaPTzhaxJm1kQSjZbMLIiYUHJ2jp7X0+C5tfmMl hf0lhX7nkY1lo3maqnc9zJ9QMvwYcoqsm2PRHH6WJmMBaeA4qgb3Gv62nUtxm50U5s 1vPUFgNDiFWOft9mhTKfU6tTbF4r4Ysbz2GaGXCU= Received: from cicely7.cicely.de (cicely7.cicely.de [10.1.1.9]) by mail.cicely.de (8.14.5/8.14.4) with ESMTP id xADMAulx017304 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Wed, 13 Nov 2019 23:10:56 +0100 (CET) (envelope-from ticso@cicely7.cicely.de) Received: from cicely7.cicely.de (localhost [127.0.0.1]) by cicely7.cicely.de (8.15.2/8.15.2) with ESMTP id xADMAuPN071117; Wed, 13 Nov 2019 23:10:56 +0100 (CET) (envelope-from ticso@cicely7.cicely.de) Received: (from ticso@localhost) by cicely7.cicely.de (8.15.2/8.15.2/Submit) id xADMAuMG071116; Wed, 13 Nov 2019 23:10:56 +0100 (CET) (envelope-from ticso) Date: Wed, 13 Nov 2019 23:10:56 +0100 From: Bernd Walter To: Ian Lepore Cc: ticso@cicely.de, freebsd-arm@freebsd.org Subject: Re: Choose between Raspberry Pi 4B 4GB and ROCKPro64 Message-ID: <20191113221056.GA43404@cicely7.cicely.de> Reply-To: ticso@cicely.de References: <20191015220433.GS96402@funkthat.com> <20191112124539.GM43404@cicely7.cicely.de> <1573571378957-0.post@n6.nabble.com> <20191112221610.GN43404@cicely7.cicely.de> <20191112225251.GB4552@funkthat.com> <20191113075343.GP43404@cicely7.cicely.de> <20191113164800.GS43404@cicely7.cicely.de> <0ad483794f3f1163a852025f4aa331efde82fb7d.camel@freebsd.org> <20191113213142.GY43404@cicely7.cicely.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Operating-System: FreeBSD cicely7.cicely.de 12.0-STABLE amd64 User-Agent: Mutt/1.5.11 X-Spam-Status: No, score=-2.9 required=4.0 tests=ALL_TRUSTED=-1, BAYES_00=-1.9 autolearn=ham version=3.3.0 X-Spam-Checker-Version: SpamAssassin 3.3.0 (2010-01-18) on spamd.cicely.de X-Rspamd-Queue-Id: 47CzMq2YC1z4MnR X-Spamd-Bar: ----- Authentication-Results: mx1.freebsd.org; none X-Spamd-Result: default: False [-5.99 / 15.00]; NEURAL_HAM_MEDIUM(-0.99)[-0.995,0]; NEURAL_HAM_LONG(-1.00)[-1.000,0]; REPLY(-4.00)[] X-BeenThere: freebsd-arm@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "Porting FreeBSD to ARM processors." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 13 Nov 2019 22:11:03 -0000 On Wed, Nov 13, 2019 at 02:37:29PM -0700, Ian Lepore wrote: > On Wed, 2019-11-13 at 22:31 +0100, Bernd Walter wrote: > > On Wed, Nov 13, 2019 at 01:42:13PM -0700, Ian Lepore wrote: > > > On Wed, 2019-11-13 at 17:48 +0100, Bernd Walter wrote: > > > > I just remembered that I own an FTDI FT4232H module. > > > > This one is capable of 12Mbps with 2k Buffers and high speed USB. > > > > I have it at a different location - guess I will have to drive > > > > and > > > > pick it up. > > > > > > You'll certainly have no trouble with the ftdi 4232. I've tested > > > those > > > at 6mpbs in both directions concurrently without any data loss. > > > > > > IMO, breaking free of the 115200 barrier is long overdue, but it > > > would > > > have been nice if the step up everyone took was to 921600, because > > > virtually all usb-serial support that. With line-level rather than > > > ttl-level adapters, 1mpbs is often the effective speed limit > > > because of > > > the cheap rs232 line-level chips they use. > > > > I don't think many USB uarts are capable to divide 48MHz into 921600 > > * > > oversampling without being off too much. > > The high speed ones are a different beast, since they likely have a > > PLL and run with an internal 480MHz clock. > > > > I don't think I've ever heard of a usb-serial chip that can't do > 921600, it's a "standard" speed (115200 * 4). The newer ftdi chips > still use an external 12mhz clock/crystal, but now they have an > internal pll that kicks it up to 60mhz, then the baudrate generator > divides that down. Ah right - I just thought about 48MHz USB, but of course that already requires a PLL. -- B.Walter http://www.bwct.de Modbus/TCP Ethernet I/O Baugruppen, ARM basierte FreeBSD Rechner uvm.