From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 31756 invoked by alias); 6 Jul 2009 12:50:23 -0000 Received: (qmail 31746 invoked by uid 22791); 6 Jul 2009 12:50:22 -0000 X-SWARE-Spam-Status: No, hits=-2.6 required=5.0 tests=AWL,BAYES_00,J_CHICKENPOX_23,RCVD_IN_DNSWL_LOW X-Spam-Check-By: sourceware.org Received: from lon1-post-2.mail.demon.net (HELO lon1-post-2.mail.demon.net) (195.173.77.149) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Mon, 06 Jul 2009 12:50:14 +0000 Received: from calivar.demon.co.uk ([83.104.54.243] helo=xl5.calivar.com) by lon1-post-2.mail.demon.net with esmtp (Exim 4.69) id 1MNne7-0006xX-af; Mon, 06 Jul 2009 12:50:11 +0000 Received: from xl5.calivar.com (localhost [127.0.0.1]) by xl5.calivar.com (Postfix) with ESMTP id D1B0A13877F; Mon, 6 Jul 2009 13:50:09 +0100 (BST) To: graham.labdon@cranems.co.uk Cc: ecos-discuss@ecos.sourceware.org References: <26049960.287991246881965794.JavaMail.nabble@isper.nabble.com> From: Nick Garnett Original-Sender: nickg@ecoscentric.com Date: Mon, 06 Jul 2009 12:50:00 -0000 In-Reply-To: <26049960.287991246881965794.JavaMail.nabble@isper.nabble.com> Message-ID: User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.3 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Mailing-List: contact ecos-discuss-help@ecos.sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: ecos-discuss-owner@ecos.sourceware.org Subject: [ECOS] Re: Serial communications X-SW-Source: 2009-07/txt/msg00023.txt.bz2 graham.labdon@cranems.co.uk writes: > Hello Nick, > Please forgive the direct approach but this issue has become a show > stopper on my project. I'm CC'ing this reply to the list, since it may be of use to others. (Of course direct one-to-one consultancy is available, at a price.) > As discussed in the forum I am unable to send more than ~128 bytes > at time to my ecos program. I am running this on the STM3210E dev > kit and have tried testing it with minicom and an program of my own. > I have tried reading the bytes as one block and reading the bytes > individually. > > within the ecos configuration tool I have set the serial buffer size > to 512 and have changed the buffer size in stm32_serial.c > > I have tried a variety of baud rates from 200 - 115200 > > Is there anything else I need to do? > have you seen serial comms (not the ecos tests) working with data > 128 bytes? The eCos test programs are a fairly good test of serial functionality. That, after all, is what they were designed to do. Part of these tests is to exchange varying sizes of data from a few bytes to several K. These are all checked for integrity. You may simply be suffering from the slowness of the external SRAM. When you consider that you are fetching every instruction and reading/writing all data over the same 16 bit external memory bus, without any caches or prefetch buffers, then performance will not be great. The STM32 is very much oriented to running code out of on-chip flash. You may need to switch to a ROM based application in order to get full speed from the device. If you have a working RAM application, switching to ROM startup should be easy. Of course a JTAG debugger would make this very easy. -- Nick Garnett eCos Kernel Architect eCosCentric Limited http://www.eCosCentric.com The eCos experts Barnwell House, Barnwell Drive, Cambridge, UK. Tel: +44 1223 245571 Registered in England and Wales: Reg No: 4422071 -- Before posting, please read the FAQ: http://ecos.sourceware.org/fom/ecos and search the list archive: http://ecos.sourceware.org/ml/ecos-discuss