Post by thread:[PIC]:F877 to 18F? (more I/O)

I've outgrown the I/O on the F877 (yes I know i can expand it using I2C) so I am looking at the next size up. Looks as if the 18F6525 might be a good choice...comments? _________________________________________________________________ From will you? to I do, MSN Life Events is your resource for Getting Married. http://lifeevents.msn.com/category.aspx?cid=married -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.

>I've outgrown the I/O on the F877 (yes I know i can expand it using I2C) so >I am looking at the next size up. Looks as if the 18F6525 might be a good >choice...comments? What sort of I/O do you need. Could you do it using shift registers? What sort of devices do you have attached (I am thinking that if you have an LCD then using Mike Predkos 2 line interface may save some pins)? -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.

>-----Original Message----- >From: al smith [spam_OUTmicro_eng2TakeThisOuTHOTMAIL.COM] >Sent: 22 June 2004 13:36 >To: .....PICLISTKILLspam@spam@MITVMA.MIT.EDU >Subject: [PIC]:F877 to 18F? (more I/O) > > >I've outgrown the I/O on the F877 (yes I know i can expand it >using I2C) so I am looking at the next size up. Looks as if >the 18F6525 might be a good choice...comments? I would not hesitate to move onto the 18F series whilst you have the chance. They are better in virtualy every respect (apart from perhaps price). The 18F6525 is a newer device that (hopefully) doesn't suffer from the problems of the first generation parts and gives a good increase in I/O and peripherals. There are a couple of things to watch for. One that I found annoying is the much lower input impedance of the A/D peripheral, a maximum source impedance of just 2.5K is recommended, compared to 10K for the 16F parts. Some of the SFR names have changed slightly as well, usualy because there is more than one of the peripheral that it refers to. Regards Mike ======================================================================= This e-mail is intended for the person it is addressed to only. The information contained in it may be confidential and/or protected by law. If you are not the intended recipient of this message, you must not make any use of this information, or copy or show it to any person. Please contact us immediately to tell us that you have received this e-mail, and return the original to us. Any use, forwarding, printing or copying of this message is strictly prohibited. No part of this message can be considered a request for goods or services. ======================================================================= Any questions about Bookham's E-Mail service should be directed to postmasterKILLspambookham.com. -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.

I need direct control I/O rather than using an I2C or shift register (already using a 16bit I2C for some other things) for controlling various FETs and feedbacks. The additional I/O is also being required for future expansion as well. So the F6525 seems like a good choice? {Quote hidden}>From: "Alan B. Pearce" <.....A.B.PearceKILLspam.....RL.AC.UK> >Reply-To: pic microcontroller discussion list <EraseMEPICLISTspam_OUTTakeThisOuTMITVMA.MIT.EDU> >To: PICLISTspam_OUTMITVMA.MIT.EDU >Subject: Re: [PIC]:F877 to 18F? (more I/O) >Date: Tue, 22 Jun 2004 14:04:41 +0100 > > >I've outgrown the I/O on the F877 (yes I know i can expand it using I2C) >so > >I am looking at the next size up. Looks as if the 18F6525 might be a >good > >choice...comments? > >What sort of I/O do you need. Could you do it using shift registers? What >sort of devices do you have attached (I am thinking that if you have an LCD >then using Mike Predkos 2 line interface may save some pins)? > >-- >http://www.piclist.com hint: The PICList is archived three different >ways. See http://www.piclist.com/#archives for details. _________________________________________________________________ Watch the online reality show Mixed Messages with a friend and enter to win a trip to NY http://www.msnmessenger-download.click-url.com/go/onm00200497ave/direct/01/ -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.

At 07:33 AM 6/22/2004 -0700, you wrote: >I need direct control I/O rather than using an I2C or shift register >(already using a 16bit I2C for some other things) for controlling various >FETs and feedbacks. The additional I/O is also being required for future >expansion as well. > >So the F6525 seems like a good choice? I've used the F8520 in a couple of instrument designs recently... really nice having those 80 pins, and the cost is pretty reasonable if the 16Kx16 code memory is enough for you. Best regards, Spehro Pefhany --"it's the network..." "The Journey is the reward" @spam@speffKILLspaminterlog.com Info for manufacturers: http://www.trexon.com Embedded software/hardware/analog Info for designers: http://www.speff.com -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.