[FWD] Project PENTAGON-1024 SL

============================================================================== * Forwarded by Wladimir Bulchukey (500:95/462) * Region : ZX.SPECTRUM (Speccy - rulez!) * From: Ruslan Abdullaev, 2:5020/400 (27 May 04 17:24) * To: All, * Topic: Project PENTAGON-1024 SL ============================================================================== From: Ruslan Abdullaev haugh All. The original is located at http://pentagon1024.narod.ru/ The best way to keep your friends is not to betray them. (From ZX-Format #8) Project PENTAGON-1024 SL Attention to all those interested in ZX-Spectrum hardware!!! A difficult time has come for Spectrum. The platform exists practically based on sheer enthusiasm, there are no serious developments in areas of _iron_. However, people, oddly enough, do not lose interest in the Spectrum (judging by what is happening on the Internet). Modern software products in the field of ZX-Spectrum, offering more and more new opportunities, demanding more and more new resources, while mass production of _iron_ finished a long time ago. Way out of this situation suggests itself _ everyone who can (and who is not too lazy) attacking their computer with a soldering iron at the ready. The results of such _experimental developments_ arevery different (you can create SOMETHING unique, or you can in a fit of uncontrollable rage after another unexpected incident, throw everything to hell). In order to somehow compensate for the sad situation, it was the decision was made to create a new Spectrum-compatible computer, satisfying the requirements of most users. Immediately it was decided to base it on a Pentagon-128 class vehicle K (1993), which according to most users is the most original domestic development in the region ZX-Spectrum. There are no unnecessary bells and whistles (like ATM-Turbo, ZX-Next or Profi), there are no glitches associated with incompatibility with the original ZX-Spectrum and brakes due to too long INT signal, familiar to Scorpion users or the same ATM-Turbo. Now we are intensified preparation for PCB layout a computer that is a clone of the ZX-Spectrum class PENTAGON. The internal structure of the computer has already been fully thought out (as close as possible to the PENTAGON-128K developed in 1993). The circuit diagram at this moment (05/24/2004) is 80% ready. Main characteristics of the computer: - RAM capacity 1 MB. (SIMM module is used). Managed ports #7FFD and #1FFD. Port #1FFD switching bitsRAM pages are the same as in KAY-1024 class machines. It is possible to disable the ROM from the 0th page and connecting the 0th page of RAM instead. In order to ensure the functionality of the programs, the authors which use a lame method of switching RAM pages (OUT #FD,A) port #1FFD has a latch similar to 48K latch in port #7FFD. - Sweep parameters and signal duration INT completely correspond to PENTAGON-128K. - Kempston Joystick and Kempston Mouse devices are recognized standard input interfaces and integrated into the system fee. - For connecting peripheral devices (primarily hard drive) there is a system bus, the wiring of which corresponds to the Nemo Bus developed by Nemo. (There may be slight differences due to the very original circuit solutions used by Nemo). The most loaded bits of the processor address bus before connections to the system bus are buffered. The drive controller is located on the system board. (It doesn't matter you can’t do without it even when using a hard drive; after all There’s nothing else to copy onto the screw for now). As mentioned above, the circuit is 80% ready. Since I student, and it’s time for the session, then at the time of taking tests andexams (i.e. for almost the whole of June), work on the project will be suspended, but after passing everything that can and should be passed, work will continue. ATTENTION! I am extremely interested in the opinion of Spectrumists regarding my project. If, after reading all this, there are people READY TO BUILD this computer for yourself when it becomes available divorced printed circuit board, or just people who are interested in all this the matter is not on the drum, then a huge request to send feedback and offers on KingOfEvil(a)yandex(dot)ru. For those interested, I can offer the following options: As soon as the wired board appears, I will be able to order at making several copies, and after I make the prototype itself and I’ll mute everything, I can provide it to everyone those who want ready-made blank printed circuit boards (at a price manufacturer) and the necessary firmware. (If you live in Moscow or the region, then there will be no problems with this). Scheme and everything documentation will be published on this site by then. For those who want to order production themselves printed circuit board, I will provide photo templates or PCB free of charge file with a wired board. I ask everyone who was not indifferent to these lines send feedback and suggestions to KingOfEvil(a)yandex(dot)ru. I will try to answer everyone and take into account all your wishes.Zhabin Alexey, 05/24/2004. P.S. As the project progresses, more information will appear on this site. updates, and soon I will publish the first version electrical circuit diagram. ra.id ================================================================================ Don't slaughter the cash cow that lays golden eggs, All...! Threat!!!!! With the best - Wlodek # wlblack(@)newmail.ru # http://wlodeks.narod.ru [ZX] [500:95/462@ZXNet] [2:5016 Forever] [Golyanovo] [Old Russians]