In message <003101c46f76$1e5e3110$0300a8c0@billnye> Jamie Morken writes: >----- Original Message ----- >From: "Steve Wiseman" >To: >Sent: Wednesday, July 21, 2004 2:54 AM >Subject: Re: [Balloon] Balloon3 - PXA version >> 19/07/2004 15:01:53, "David Bisset" >> wrote: >> >> >Steve, >> >Can we know what's currently on the PXA version, or in your >> head... >> >(delta from 2.05/2.06)? ..... >> At the moment, I'm tending towards the 27X, any comments from >> the list? > >I think the PXA27x series is great too :) The only problem I have heard >about it is that >it may be a short production run and thus may not be available for very >long, this is because >it is made not for the broad market but for just PDA's (this is what my >local Intel rep has told >me). I like the PXA271 the best as it has 32MB sdram and 32MB flash built >in to it. For quite a few applications that is more than enough. The only times I make sure I put embedded projects with extra RAM is where I have video processing (dual ported) in one case an external Flash and SRAM for some high speed image processing functions. > I don't >think this is enough sdram for most people but it is tempting to avoid the >external ram and flash Depending on code complexity the Flash may be small, but some networking or the USB data buffering may eat up RAM. >interfaces and make a simple board with just the power and JTAG routed and >SPI/I2C and >have a high performance 32bit controller for embedded projects like >robotics! Does look good in that respect, having used various micros with several built in peripherals. > I have made an >eagle cad library package for the pxa271/2/3 (pxa270 has a different >package), and the pin pitch >is really quite small (0.65mm) whereas the pxa255 has 1.0mm pitch. Not the worst of sizes, and that pin pitch is quite large for [T]QFP devices I have an Eagle CAD library available on http://www.gnuh8.org.uk/ that has Renesas chips where pin pitch of 0.5mm and even 0.4mm pitch is quite common. I have built prototypes by hand with JBC iron and 0.2mm or 0.4mm tip size using some of these chips. > So this could make it harder to route and may require a more expensive >PCB with microvias. I am interested in helping out (if you are accepting >volunteers!) whether you choose a PXA255 or PXA27x for your next board. However if you have an Eagle library make it available to the download section of Cadsoft website. If I have time I may be able to help out in some ways if there is a Protel/Eagle exchange method. Not looked for one yet. Artwork could always be reviewed to check dimensions etc. by others in Gerber formats. When you say microvias, I wonder what size you mean, having done some boards with 0.2mm drill vias. Blind vias might be a different matter. Some of the easiest method for PCB prototyping I use is people like Beta Layout (www.pcbpool.com) as I can send the Eagle (also Protel and other files) and do some large number of layers as well. Not checked capabilities on blind vias and min via size recently. -- Paul Carpenter | paul@pcserv.demon.co.uk Main Site GNU H8 & mailing list info For those web sites you hate