From PICLIST@MITVMA.MIT.EDU Fri Nov 15 05:37:06 2002 Received: from cherry.ease.lsoft.com [209.119.0.109] by dpmail10.doteasy.com with ESMTP (SMTPD32-7.13) id A88217C200A6; Fri, 15 Nov 2002 05:37:06 -0800 Received: from PEAR.EASE.LSOFT.COM (209.119.0.19) by cherry.ease.lsoft.com (LSMTP for Digital Unix v1.1b) with SMTP id <16.007DB89F@cherry.ease.lsoft.com>; Fri, 15 Nov 2002 8:23:02 -0500 Received: from MITVMA.MIT.EDU by MITVMA.MIT.EDU (LISTSERV-TCP/IP release 1.8d) with spool id 2220 for PICLIST@MITVMA.MIT.EDU; Fri, 15 Nov 2002 08:22:55 -0500 Received: from MITVMA (NJE origin SMTP@MITVMA) by MITVMA.MIT.EDU (LMail V1.2d/1.8d) with BSMTP id 9132; Fri, 15 Nov 2002 08:22:28 -0500 Received: from kona.reonbroadband.com [66.51.65.3] by mitvma.mit.edu (IBM VM SMTP Level 320) via TCP with ESMTP ; Fri, 15 Nov 2002 08:22:28 EST X-Comment: mitvma.mit.edu: Mail was sent by kona.reonbroadband.com Received: from mail.embedinc.com (86-66-51-66.reonbroadband.com [66.51.66.86]) by kona.reonbroadband.com (8.9.3/8.8.7) with SMTP id IAA14158 for ; Fri, 15 Nov 2002 08:22:32 -0500 Received: from 192.168.0.3 (main) by mail.embedinc.com ; 2002 NOV 15 08:20:49 EST References: <004b01c28c23$51b8ba40$6501a8c0@potshe01.pa.comcast.net> <006401c28ca1$b0a4aa40$6501a8c0@potshe01.pa.comcast.net> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2600.0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2600.0000 Message-ID: <009101c28caa$1eec0b30$0300a8c0@main> Date: Fri, 15 Nov 2002 08:23:00 -0500 Reply-To: pic microcontroller discussion list Sender: pic microcontroller discussion list From: Olin Lathrop Subject: Re: [PIC]: 16F627 brown out? question To: PICLIST@MITVMA.MIT.EDU X-RCPT-TO: Status: R X-UIDL: 277600645 X-Evolution-Source: pop://mailinglist%40farcite.net@mail.farcite.net/ X-Evolution: 0000075a-0000 > Ok.... did I: 1. stump the list (doubt it) 2. ask such a stupid > question that it does not deserve an answer (probably) or 3. upset > someone without any knowledge of doing so??? I didn't answer because you left out too much important information and I didn't feel like playing twenty questions. It was easier to just hit delete and move on. > > I have a 16F627 that appears to be sitting in some form of brownout. The > oscillator is running, but she ceased executing code. What oscillator mode? What frequency? How do you know it's in "brownout"? What voltage exactly it it running at? > > Unfortunately, none of the fancy power up controls are enabled. MCLR is > disabled in the program fuses, along with the brown out detect and the power > up timers. If brownout detect is disabled, it can't be in "brownout mode", although the power voltage can be too low for proper operation. Again, what exactly is the power voltage? > Did I remember to > tell you that the power supply powers up and down twice a second!!!!!) No, you didn't. So this condition only last 1/2 second? What does the chip do when power comes back? Does the power go all the way to 0 and 5V? What is the rise time? > > From this I gather she has gone into a brown out mode. I can't gather that from the information you supplied. > Here is my exact > question: If in brown out, will the WDT cease to function? Or should it > apply a reset and get everything running again??? The WDT should function normally as long as the power voltage is at the minimum operating level. The entire chip, including the WDT, may act out of spec below that. ***************************************************************** Embed Inc, embedded system specialists in Littleton Massachusetts (978) 742-9014, http://www.embedinc.com -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.