This message generated a parse failure. Raw output follows here. Please use 'back' to navigate. From devnull@lkml.org Thu Apr 25 09:40:34 2024 Delivery-date: Fri, 18 Aug 2006 20:05:54 +0000 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932487AbWHRUF2 (ORCPT ); Fri, 18 Aug 2006 16:05:28 -0400 Received: from spirit.analogic.com ([204.178.40.4]:30987 "EHLO spirit.analogic.com") by vger.kernel.org with ESMTP id S932315AbWHRUF1 convert rfc822-to-8bit (ORCPT ); Fri, 18 Aug 2006 16:05:27 -0400 Received: from chaos.analogic.com ([10.112.50.11]) by phoenix.analogic.com with Microsoft SMTPSVC(6.0.3790.211); Fri, 18 Aug 2006 16:05:26 -0400 Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT X-MimeOLE: Produced By Microsoft Exchange V6.5.7226.0 Received: from chaos.analogic.com (localhost [127.0.0.1]) by chaos.analogic.com (8.12.11/8.12.11) with ESMTP id k7IK5Pl5020010; Fri, 18 Aug 2006 16:05:25 -0400 Received: (from linux-os@localhost) by chaos.analogic.com (8.12.11/8.12.11/Submit) id k7IK5Kav020009; Fri, 18 Aug 2006 16:05:20 -0400 X-OriginalArrivalTime: 18 Aug 2006 20:05:26.0137 (UTC) FILETIME=[A53EAE90:01C6C301] content-class: urn:content-classes:message Subject: Re: Serial issue Date: Fri, 18 Aug 2006 16:05:20 -0400 Message-Id: In-Reply-To: <1155928885.2924.40.camel@mindpipe> X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: Serial issue Thread-Index: AcbDAaVII8yyFmlYSkKrFpcayzkxxQ== References: <1155862076.24907.5.camel@mindpipe> <1155915851.3426.4.camel@amdx2.microgate.com> <1155923734.2924.16.camel@mindpipe> <44E602C8.3030805@microgate.com> <1155925024.2924.22.camel@mindpipe> <1155928885 From: "linux-os \(Dick Johnson\)" To: "Lee Revell" Cc: "Paul Fulghum" , "linux-kernel" , "Russell King" Reply-To: "linux-os \(Dick Johnson\)" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 18 Aug 2006, Lee Revell wrote: > On Fri, 2006-08-18 at 15:15 -0400, linux-os (Dick Johnson) wrote: >> A file-transfer protocol??? Has he got hardware the __required__ >> hardware flow-control enabled on both ends? One can't spew >> high-speed serial data out forever without a hardware handshake. >> > > Interesting you should mention that. As a matter of fact I have to > disable all flow control or the serial console doesn't even work. I > considered this a minor issue and had forgotten about it. > > But, in polled mode with no flow control I can transfer a 10MB file. > There are a lot of retransmits but it works. > > Lee > Using RS-232C for file transfer and as a serial console are two different things. Many terminals and terminal emulators don't even activate RTS/CTS. If you are just getting data from the output of a UART to view on a screen, the data usually comes in spurts, a line at a time, and a screen at a time. There is plenty of time for the receiving terminal to write the stuff to the screen. However, with file transfers, data streams with no breaks. There needs to be time for these buffers of data to be written to files, etc., or else you eventually run out of buffers even if no interrupts are ever lost. Therefore, you must use hardware handshake. In other words, you need to connect your machines together with a complete null-modem cable, not just three wires. Then both machines need to cooperate, i.e., the receiving machine needs to lower CTS before its buffers get full and the sender, must look at its RTS bit and wait for it to go false before sending anymore data. Failure to do this __will__ result in lost data. Cheers, Dick Johnson Penguin : Linux version 2.6.16.24 on an i686 machine (5592.62 BogoMips). New book: http://www.AbominableFirebug.com/ _  **************************************************************** The information transmitted in this message is confidential and may be privileged. Any review, retransmission, dissemination, or other use of this information by persons or entities other than the intended recipient is prohibited. If you are not the intended recipient, please notify Analogic Corporation immediately - by replying to this message or by sending an email to DeliveryErrors@analogic.com - and destroy all copies of this information, including any attachments, without reading or disclosing them. Thank you. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/