On 25/11/04 at 21:07 Dave P wrote: >> The QL uses such minimal power that unless we are using Coldfire this >> can be ignored. > >Not so. On the typical PC laptop motherboard is a charge control circuit >to regulate the current to the battery, and power monitoring to select >whether the battery is charged, used, or ignored.
Actually, the QL uses quite a lot of power by today's standards for low power devices, but definitely negligible compared to today's laptops. Using a Coldfire CPU (which has it's own problems I may find time to discuss in another email), things can only get better - the most power-hungry Coldfire uses only about 2W of power. To give you some perspective, it could run for approximately an hour and a half on an average mobile phone Li-ion battery. >hard to disagree this point) then what is really in demand is an embedded >QL-compatible platform that can be a desktop or laptop board, or used for >control/monitoring functions, etc. It would need to be a board of two >halves, logically speaking. A standard processing, OS, memory and required >interfaces half and a custom interfaces half (if that counts as half). >Ironically, this is more-or-less what Nasta designed as the Aurora II. Heh... but sometimes I really hate being right about some things ;-) As it happens, my current employer needs precisely such a device, though not as powerful computing-wise as the combo of GoldFire and Aurora II. QL compatibility is actually one of the goals - time and time again, I have demonstrated that it is a very valuable tool, usually by writing small snippets of Sbasic on QPC2 to develop control algorithms for some of his hardware (and in this case I do mean hardware, as in motors, magnets and the like). To this end I now have on my table 10 68SZ328 fully 68k compatible 'systems on a chip' - commonly known as the last DragonBall CPU, used in Palm's last series of 68k based palm-pilots. This chip is still in production, and aside for not being extremely fast (it's a 66MHz 68000), it fits the bill quite nicely. The next project we are alrerady looking at is something similar using the new V4e Coldfires. The 68SZ328 'QL' will be a small 4-layer board slightly wider than the Aurora (say, the size of the printed Quanta mag). 16M of Flash (Replaced by 32M when larger chips become available) and 64M of RAM will come as standard. Also a VGA or TFT LCD interface, CF and MMC memory card slots, serial ports, and quite possibly USB and/or Ethernet. The intention is to make these available almost at cost to the QL community in exchange for porting SMSQ/E etc. First prototypes will probably also have a QL compatible expansion port, and all can be affixed to a small VGA resolution (640 x 480) TFT LCD. >My only discomfort over Nasta's design is that he is extremely concerned >about efficiency of space. Therefore, he's crammed an awful lot into a >very small 6-layer PCB. Actually, it's 4 layer ;-) 6 Layer is not that much more expensive though - 15 to 20% has been quoted to me by the manufacturer. The only problem with said manufacturer is that it's the next country over, now part of the EU, which makes it necessary to go through rather complex customs procedures, but as my employer is looking at moving to multilayer boards anyway, it may be possible to do a 'where 4 can fit, the 5th can usually be easily shoed in' thing. >Nasta is just too efficient for his own good ;) Looking back, I'm not really that efficient at all ;-( but I hope I will improve... BTW with recent experience in doing 2 layer boards running CPUs and RAM at 100MHz, I am convinced more than ever that ANYTHING can be fitted into 4 layers ;-) Oh, and one more thing - the same recent experiences have shown again that autorouters are still abysmal at doing any sort of efficient PCB design. At least the ones I can afford... Doing the routing manually, which took about a week, admittedly, I have managed to squeeze one 160x100mm 4-layer board and one 40x100mm 2 layer board (both autorouted) onto a single 120 x 70mm 2-layer board, almost 3x less area and about 7x lower cost of manufacture. Nasta PS, special note to TF: Aurora II and GF are routed with 8.333mil wide tracks and 8.333mil spacing - so not quite to romDisq standards but then, both sides are completely covered by components ;-) _______________________________________________ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm
