Disclaimer: I don't know much about building electronics, but I believe I know enough about it to interpret what somebody else is saying about it. Of course, I may be completely wrong on the latter. :-)
I actually have some documentation on this. All quotes come from "Designing Cards and Drivers for the Macintosh Family 3/e", by Apple Computer Inc.. Here is how Apple describes it: The pinouts of the expansion connectors used on the Macintosh SE/30 and the Macintosh IIfx are nearly identical except for certain signals that are machine-specific (unique) to each computer [...] expansion cards designed for the Macintosh SE/30 and the Macintosh IIfs computers are not interchangable. [...] Once the PDS adapter card has been installed in the Macintosh IIsi, the expansion connector is physically and eectrically identical to the one found on the Macintosh SE/30. In the next section: The only differences between the two expansion card connectors are the clock speed and load limits for each signal. This implies that a card can be desinged for both machines and you do not require an adapter to account for the electrical characteristics. You do, however, depend upon a manufacturer which considered the electrical tollerances for both machines. The pinout for the IIsi card has half a dozen differently labeled pins, but the difference is minor (implying similar function, but perhaps slightly different electrical characteristics -- I don't know). The IIsi also uses about three pins which are labelled as reserved on the SE/30, but those are labelled as "for use by Apple" and they decided "not to extend this signal out to the PDS adapter card" on the IIsi anyway. Several chapters later, on the IIci: Cards designed for the Macintosh IIci cache connector are not compatible with cards designed for the general-purpose 68030 Direct Slot on other Macintosh computers. Their pinouts, form factors, clock speeds, and power budgets are different. What all of this says to me: 1) If the card plugs into the IIci sans adapter, you will need an adapter for the IIsi and SE/30. This may involve involved electronics, or it may not -- I didn't investigate quite that far. 2) A properly designed card or adapter should work in both the SE/30 and IIsi. A poorly designed card or adapter will not. Unfortunately, a poorly designed adapter may put too much of a load on the computer's circuitry -- hence cause damage. Depending on how these machines are designed, it may be possible to get an SE/30 card to work on a IIsi or vica versa (again, I didn't investigate deeply enough) but not the other way around. Also, manufacturers frequently change the design of cards without changing the model number (to reduce costs, remove bugs, etc). In otherwords, consider reports of success with caution. Byron. -- 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 ---------------------------------------------------------------
