From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 30422 invoked by alias); 27 Jan 2008 06:46:20 -0000 Received: (qmail 30413 invoked by uid 22791); 27 Jan 2008 06:46:19 -0000 X-Spam-Check-By: sourceware.org Received: from netic.com (HELO netic.com) (208.131.130.247) by sourceware.org (qpsmtpd/0.31) with ESMTP; Sun, 27 Jan 2008 06:45:58 +0000 Received: from piii550 (60-242-91-36.static.tpgi.com.au [60.242.91.36]) by netic.com (8.12.11.20060308/8.12.11) with SMTP id m0R6jZtn028690; Sat, 26 Jan 2008 23:45:38 -0700 From: "Laurie Gellatly" To: "Grant Edwards" , Date: Sun, 27 Jan 2008 06:46:00 -0000 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2911.0) In-Reply-To: X-IsSubscribed: yes 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: RE: [ECOS] Re: Uart missing chars when in Release X-SW-Source: 2008-01/txt/msg00174.txt.bz2 Hi Grant, >> I have an LPC2112 UART0 running at 117K (2112 does not have >> the fractional divider, 2112/01 does). >> >> I'm sending it 100 characters (1 to 100) at that baud and >> printing out the characters after they have all arrived. >Arrived where? Sending from where? Coming from a LPC2103 not running eCos. >Is eCos running on both the sending and receiving device? Are >the "missing" caracters actually on the wire or not? (That >would tell you whether it's the sender's fault or the >receiver's fault). The missing chars are on the wire - I've snooped them. >> I get consistently 100 chars arriving when the app is run in >> RAM under debug in eclipse. When running the Release code from >> flash, about 30% of the time I get less than 100. By less I >> mean up to 14 characters less. The missing characters are >> typically together in 1 or 2 bursts. >> >> I can't spot what is making the difference. >I'm not familiar with your platform, but on many platforms >running from flash can be much, much slower than running from >RAM -- in some cases up to maybe 8-10X slower, but 4X slower is >more typical. Flash often has much slower access times that >RAM and is often narrower than RAM. 2X bus cycles with 4X >access time can add up pretty fast. The same platform also runs an Ethernet interface without problems. 10Mbit is quite a bit faster than 115K baud so I feel I can probably discount that. >Are you seeing rx overrun errors? If the rx end is running too >slowly for the data rate, you would see rx overrun errors. >From what I've read, the OE gets cleared on each read of RBR. How can I check on this? Is there a counter of OE and other errors kept in eCos that I can access? Thanks ...Laurie:{) -- Before posting, please read the FAQ: http://ecos.sourceware.org/fom/ecos and search the list archive: http://ecos.sourceware.org/ml/ecos-discuss