> Date: Thu, 15 Apr 2004 12:19:00 +0800 > From: John Niven <[EMAIL PROTECTED]> > .....so PDS slots.... > > They look alike (same connector) but apparently are not. Specifically, > > 1) SE/30 > 2) IIsi > 3) IIci > > I believe 1) and 2) are compatible as they can both use the same Asante > NIC PDS card. But 3) apparently needs an adapter of some kind to run a > DayStar accelerator. I found a description of the pinouts for the SE/30 > PDS (and presumably the IIsi) here:
> Anybody know anything? 1) and 2) are very similar but there are a couple of signals which are different. Fortunately, these either don't usually matter or the card designers took that simple difference into account to make their cards more widely compatible. 3) is fairly different. Most late model Daystar cards were built to run in the IIci slot without an adapter. The machines with PDS slots different from the IIci's require adapters. But some early Daystar products were machine specific before they went to the PowerCache with Adapter scheme and then the Turbo040 with adapter scheme. So you never know what kind of bizarre early Daystar product you'll turn up, but it will probably be well engineered. The definitive reference on this is Apple's "Designing Cards and Drivers for the Macintosh" 3rd edition from Addison Wesley. It has the PDS slot pinouts and a lot of detail on implementing expansion cards. I picked up a copy for about $10 plus shipping last year. and: > Date: Thu, 15 Apr 2004 13:13:26 +0800 > From: John Niven <[EMAIL PROTECTED]> > Thanks Luke, > > but somethings wrong somewhere. To quote the second article: > > "Apple got a lot of use out of the 68030 PDS. The one in the SE/30 ran > at 16 MHz, the one in the IIci at 25 MHz, the one in the IIsi (Oct. > 1990) at 20 MHz, and the one in the IIfx (March 1990) at a blistering > 40 MHz. Except for bus speed, these were electrically identical, so it > was often the case that the same card would work in the SE/30, IIsi, > and IIci." > > This definitely contradicts all else I've read about IIci accelerators > in an SE/30! It's difficult to tell from quoted material, but the article quoted above is either unclear, misquoted or at least wildly inaccurate. The speeds quoted above are correct for the 68030 CPU. However, the IIci has a different PDS pinout than the other three models listed and there are minor variations even between those other three. The IIfx PDS slot only runs at 20 MHz (although the CPU runs at 40MHz), and according to "Designing Cards and Drivers for the Macintosh" it should work with pretty much any card that works in the IIsi PDS slot. I suspect the latter statement is also inaccurate as I don't believe that the Turbo040 (e.g.) will work in the IIfx PDS slot. But the CPU upgrade PDS cards are a different animal from the kind of thing that Apple's engineers probably invisioned when they wrote that book. So an interesting test would be to install an SE/30,IIsi ethernet card in the IIfx PDS slot and see if it works. The IIfx has a weird (at the time) architecture where the CPU and memory were on one bus at 40MHz and the entire I/O system was on another bus running at half the speed. Jeff Walther -- Compact Macs is sponsored by <http://lowendmac.com/>. Support Low End Mac <http://lowendmac.com/lists/support.html> Compact Macs list info: <http://lowendmac.com/lists/compact.shtml> --> AOL users, remove "mailto:"; Send list messages to: <mailto:[EMAIL PROTECTED]> To unsubscribe, email: <mailto:[EMAIL PROTECTED]> For digest mode, email: <mailto:[EMAIL PROTECTED]> Subscription questions: <mailto:[EMAIL PROTECTED]> Archive:<http://www.mail-archive.com/compact.macs%40mail.maclaunch.com/> --------------------------------------------------------------- >The Think Different Store http://www.ThinkDifferentStore.com ---------------------------------------------------------------
