CompuServe Thread

#Rejuvenator Tech Info

7 messages in this thread
#108962From: Chris ScheersJun 17, 1990 12:28 AM
I've noticed some of the messages concerning stability of the Rejuvenator and Rejuvenator/LUCAS incompatibilities. Since I am running a LUCAS board, this concerns me a bit. Does the Rejuvenator come with enough technical documentation to allow a knowlegable user to trouble shoot? Has there been any more consideration of a bare board with tech info? Thanx – Chris PS – Thanx for the help on the Conner.
#109000From: Gregory B. TibbsJun 17, 1990 9:03 AM
Lucas compatibility is very important to me as the people who built LUCAS are the ones most likely to want to keep their A1000 and a high percentage are likely Rejuvenator owners. The stability issue is a problem in manufacturing QA which has been resolved. The only problem actively biting me is LUCAS. As I said before, I'm up to 40-50% reliability. I want 100%. I've one report of a LUCAS owner getting his to work reliably by itself, but doesn't when Frances is added. Bare board will not be coming soon. It requires some fairly hard to find parts that would be expensive if purchased in low quantities. CBM might not like it also. I am working on an expansion bus buffer kit that will be bare board. The manual is aproximately 20 pages and contains more information than the typical manual from other vendors. It goes out of its way to list all the major pitfalls that you may run against, which very few manufacturers put in print. It does not include a schematic as that is propreitary. -Greg
#109062From: Phil SaundersJun 17, 1990 8:53 PM
Greg–I have a LUCAS/FRANCES board that I've been trying to get running. I recently installed the 1.3 ROM upgrade published in amazing computing (which involves removing the daughterboard and installing a ROM socket. I cheated by using back to back sockets and not removing the daughterboaRD connector pins, so the mod is reverible and I can add Rejuvenator at a future time. Antyway the new PAL chips are faster than the old setup. I have gotten LUCAS/FRANCES working fairly well at 12 MHz, but am having compatibility problems with LUCAS/FRANCES and my XETEC HD and Ramboard. I suspect the faster PALs are altering the syste timing just enough to throw off the HD and ramboard. They sometimes work at 12 M but the system won't boot at faster clock speeds. Anyway I mention this to you in case it helps with your debugging of rejuvenator and because you mentioned to me at AmiExpo that a new capacitor might be needed to improve LUCAS/ HD compatibility with rejuvenator. I assume we'd be talking about a cap to delay AS slightly. Anything further on that? Good luck.
#109136From: Gregory B. TibbsJun 18, 1990 7:04 AM
The problem is that the UDS and LDS comming out of LUCAS is apparently incompatible with the new Agnus. It uses this signal for RAS CAS generation to the chip RAM, for example. I have tried much slower PALs with no difference in performance, So overall timing is OK. My particular LUCAS will boot at 16, 20Mhz with any technology 7474 at U9 when it is hooked to the original daughterboard. It works really well. As such, it works about 40-50% of the time with teh Rejuvenator. -Greg
#109170From: Phil SaundersJun 18, 1990 3:22 PM
Well that doesn't help me, since I'm using the original agnus. I hope you can get it worked out. good luck.
#109091From: Chris ScheersJun 17, 1990 11:03 PM
I think that you had said that the problem with the LUCAS was that the PALs were too slow. I've been looking at making some changes to the LUCAS and I will probably use PEEL devices. These are available down to 10ns, I believe. If using these higher speed parts doesn't break the LUCAS, would that help the Rejuvenator? Chris
#109137From: Gregory B. TibbsJun 18, 1990 7:04 AM
The speed of the PALs used by LUCAS, particularly U6, is sensitive to being changed. It directly affects the 7474 technology selection at U9. Therefore a 25 nsec PAL must be used or you will get out of the range that works. -Greg