---- START NEW MESSAGE --- Received: from cherry.ease.lsoft.com [209.119.0.109] by dpmail10.doteasy.com with ESMTP (SMTPD32-8.05) id AD3811D5006C; Fri, 30 Jan 2004 15:48:08 -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 <4.00CC59C1@cherry.ease.lsoft.com>; Fri, 30 Jan 2004 18:47:55 -0500 Received: from MITVMA.MIT.EDU by MITVMA.MIT.EDU (LISTSERV-TCP/IP release 1.8e) with spool id 8399 for PICLIST@MITVMA.MIT.EDU; Fri, 30 Jan 2004 18:27:17 -0500 Received: from MITVMA (NJE origin SMTP@MITVMA) by MITVMA.MIT.EDU (LMail V1.2d/1.8d) with BSMTP id 4502; Fri, 30 Jan 2004 18:26:58 -0500 Received: from *unknown [64.4.26.97] by mitvma.mit.edu (IBM VM SMTP Level 430) via TCP with ESMTP ; Fri, 30 Jan 2004 18:26:26 EST X-Warning: mitvma.mit.edu: Could not confirm that host [64.4.26.97] is hotmail.com Received: from mail pickup service by hotmail.com with Microsoft SMTPSVC; Fri, 30 Jan 2004 15:21:15 -0800 Received: from 67.65.155.200 by bay8-dav40.bay8.hotmail.com with DAV; Fri, 30 Jan 2004 23:21:15 +0000 X-Originating-IP: [67.65.155.200] X-Originating-Email: [jsears2027@hotmail.com] X-Sender: jsears2027@hotmail.com References: <27F5AF5F2C1BD2119F860008C7F4730A0853C52B@co-srv06.ridgid.com> 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 6.00.2800.1158 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1165 X-OriginalArrivalTime: 30 Jan 2004 23:21:15.0566 (UTC) FILETIME=[C1DE04E0:01C3E787] Message-ID: Date: Fri, 30 Jan 2004 17:21:12 -0600 Reply-To: pic microcontroller discussion list Sender: pic microcontroller discussion list From: James Nick Sears Subject: Re: [PIC:] 16LF877A A/D To: PICLIST@MITVMA.MIT.EDU Precedence: list X-RCPT-TO: Status: U X-UIDL: 371856604 Well looks like it is confirmed. I set the A/D to use Vdd for Vref+ and got 0.145V in my PC software, which divided by VRefOld = 1.25, times Vdd = 4.75 gives 0.58V, the correct value. I just need to order a 2 or 2.5V reference and I should be good to go. Thanks to everyone for their help. Nick ----- Original Message ----- From: "James Nick Sears" To: Sent: Friday, January 30, 2004 4:58 PM Subject: Re: [PICLIST] [PIC:] 16LF877A A/D > Thanks. I found it in the 877A datasheet and while that is good news, there > is another spec for VREF = (Vref+ - Vref-) that has a minimum of 2V. Looks > like I need a different reference. > > I reprogrammed the working board so I know all the firmware is the same and > it still works so it has to be a hardware issue and I guess that's probably > it. I'm getting ready to reprogram one of the faulty boards to use Vdd as > the reference and see what results I get. BRB. > > Nick > > > > ----- Original Message ----- > From: "Eisermann, Phil [Ridg/CO]" > To: > Sent: Friday, January 30, 2004 4:22 PM > Subject: Re: [PICLIST] [PIC:] 16LF877A A/D > > > > pic microcontroller discussion list wrote: > > >> Are you sure about that? The data sheet says MIN (Vdd-2.5V), and > > >> MAX (Vdd+0.3V). > > > > > I couldn't find that in the datasheet. What page is it on? > > > > In my version of the datasheet (DS30292A), it is Table 15-13 on > > page 175 and labeled parameter A21 > > > > > What exactly does the label of that graph on p.210 mean though > > > ("Differential or Integral Nonlinearity (LSB)")? > > > > see microchip's app note AN546 for a description. Based on a different > > chip but does explain the terms. I suspect a google would turn up > > a lot more information. > > > > Phil Eisermann > > > > -- > > http://www.piclist.com#nomail Going offline? Don't AutoReply us! > > email listserv@mitvma.mit.edu with SET PICList DIGEST in the body > > > > -- > http://www.piclist.com#nomail Going offline? Don't AutoReply us! > email listserv@mitvma.mit.edu with SET PICList DIGEST in the body > -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body .