On 1/11/02 at 5:11 PM Dexter wrote: > functionality for that low cost. If we made a board that includes [regular > IO card] functionality and additional functionality, we have to do a cost > benefit analysis to decide if it would be cheaper to do it as one board, or > omit the functionality that's included in the generic board and only include > the novel features. (I know what I mean, I hope you do!)
Certainly :-) > The main benefit of having EVERYTHING on one card is that it leaves a slot > free. But, for what? For size reduction. Look at the MinisQ60 prototype on Peter's site. Also, just in case :-) with the ease of programming under Sbasic, some specialized 'boxes' based on a Q40 could be made... > I think we should investigate the option of not duplicating the work > that is already done for us using the generic multifunction card, > and concentrate on those novel facilites that aren't already included. Unless these overlap. Let me give you an example: Dual IDE is actually a very desirable option, when the CF card comes into play. One channel for the hard drive and D ROM, one for the CF, say. Maybe there is interest in PS/2 mice, since serial seem to be becoming extinct (though this argument is the same as the ISA IO cards becoming extinct...). If we have a device that does both, and other things we might already have on another board, for the price of implementing one, it's worth duplicating things. A stretched argument here, but I'm trying to illustrate a point. Certainly a card with Ethernet and 16 bit sound would be an interesting one, without the IO. Here the argument of dissapearing ISA is quite valid, as one would have to look for _speciffic_ ISA cards, whereas the requirement for an IO card is far more relaxed. But a cost vs benefit study would have to be done to see if the duplication of features while already having a board with chips on it, becomes a signifficant investment. For instance, on some occasions squeezing another device on a board, even just 'in case' and not soldering it on, presents an insignifficant manufacturing cost (of course, it is a development cost, but in the QL world, forget about even factoring that in - if we did, nothing would ever be done). The fact that designing _another_ card for a system with two slots, would also has to figure in there somewhere. >> 1) Will this thing ever be plugged into the real ISA (IMHO, hopefully >> not!) >I doubt it. Who would write windows drivers? Windows is not a concern at all. But there are embedded PCs out there, and there is the Linux aspect to this. Unlikely, but worth a two minute think. Also, how much does the board REALLY have to look like a regular ISA board, taking it's usage into account, which would primairly be Q40/60? >> 5) Feedback to original GF design - decisions made in the design of the >> IO board might override some of the ones made for the design of GF IO (a >> 'let's meet in the middle' effort) if it simplifies matters with making >> the drivers more uniform across platforms. >...The trick (and hence all the discussion) is to devise a plan for the >circuitry that will make it logically appear the same (or as similar as >possible) to the Q60 *and* the Goldfire. Sure, the boards may look >different, and may have different components, but that doesn't matter as >long as they look the same to the processor and operating system. They even do not have to be really similar to the very last bit. Things like different addresses for the various control registers are very easy to compensate for, unlike larger issues like completely different interrupt structure. >> Care to take up the challenge of making it a two-layer board? It would >> certainly make it MUCH cheaper... However, 4 layers make it MUCH easyer >> to route, and may also make the whole thing smaller... >Hmmm. I'm more comfortable with a 4-layer board, because IDE could pick up >noise in a multi-function card environment, and because space really will >be at a premium. To give you an idea of the existing implementation, without IDE though: it only takes about 9 square inches, including the connectors, but that is on 4 layers. Te added cost of 4 layers may well be offset by the ability to make the board smaller, unless you find a board manufacturer that gives a particulairly good price for a 'standard' board size. >If you want lucrative, help me with an ARM-based SBC - they're all the >rage for embedded linux, wearable computing, STBs and, well, groovy stuff. >And relatively similary in :o) And it could run linux, And run uQLx on >that at original QL speed and then some. (Ahhh, stoppit Dave!) Well, that's really for off list email... > I checked, but my search produced only the fact that the ISA > implementation ignores a few signals that are exotic and/or > unnecessary in their application. How about a pinout and > specs? :o) Not my area, I'm afraid :-))) Nasta
