CompuServe Thread

#XA fallback?

12 messages in this thread
#60746From: R. Simonsen/MicroBoticsJul 25, 1993 10:14 PM
No, it doesn't. There is no good way to do this and yet preserve access to the memory since the memory is "high" and the EC020 can't address it due to its limitations. There shouldn't be any reason to "fallback" inasmuch as all the software you should find youself using on an A1200 should be well-behaved (otherwise AmigaDOS 3.0 and AGA will not like it much either). And the 020 and the 030 are much closer in structure than the 030 and the 68000. Regards, –Redmond
#60774From: Joe BuckleyJul 26, 1993 4:12 PM
Redmond, OK, thanks, I just wanted to know about that ahead of time. No big deal. I was originally intending to get an MBX1200z, but since I now have a quite substantial credit at my deeler, I'm thinking of taking the plunge and getting an M1230XA. (That is if your people and my dealer can ever manage to get in touch with each other!) Joe
#60782From: R. Simonsen/MicroBoticsJul 26, 1993 7:33 PM
Who is your dealer, Joe? Tell him that American Software carries the XA. Also: you can buy an XA through Computer Basics/Amigaman (advertised in AmigaWorld). –Redmond
#60829From: Joe BuckleyJul 27, 1993 4:18 PM
Redmond, Thanks. For the time being, I'd like to see what kind of deal my local shop can get for me. If he can come within shouting distance of mail order, I'll go with him. (Only two good local Amiga dealers – at least that I frequent – and I'd like to keep him going.). Joe
#60837From: R. Simonsen/MicroBoticsJul 27, 1993 5:42 PM
I respect your support for your local dealer, Joe. I'm amazed you have TWO available to you. –Redmond
#60942From: Joe BuckleyJul 29, 1993 5:17 PM
Redmond, The dealer I got my 1200 from has made an offer at just about the average mail order price for the 'EC030 40/0/0 (I have a 4MB SIMM and may take the plunge for a 25 ro 33MHz FPU). By next weekend I should be able to give you my verdict on the board! 🙂 Keep up the great work. Joe
#60997From: R. Simonsen/MicroBoticsJul 30, 1993 6:14 PM
Great, Joe. Since the processor is socketed PGA style, you can upgrade to a 50MHz at some future date. BTW: I just got a load module done of AIBB benchmarks on the A4000/30 and compared it to the XA. …XA beats the bat-puckey out of the 4000/30 on all tests. –Redmond
#61008From: Robert ComerJul 30, 1993 9:05 PM
Can't wait to see how well the 50 Mhz XA does, I just ordered one. 🙂 Bob Comer — Cruising the nets on AutoPilot from Cheyenne, Wyoming
#61043From: Joe BuckleyJul 31, 1993 2:03 PM
Redmond, Yes, I should know about this by Thursday. If you get an FPU rated at or above the clock on the CPU, can you use the one clock to drive them both, or do you still need a seperate clock to drive the FPU? Oh, yeah…when you say the "XA beats the bat-pucky out of the 4000/030 on all tests", what clock speed are you running the XA at? Verses what, 25MHz for the 4000/030? Thanks. Looking forward to the new toy. Joe
#61106From: R. Simonsen/MicroBoticsAug 1, 1993 6:30 PM
We sell the XA at 33, 40, and 50 MHz. It beats the 4000/30 at all configurations. The 4000/30 is only a 25MHz EC unit (for reasons I can only guess at). Is it thus a fair comparison? Certainly on a price/performance basis it is! If you clock a faster math chip at the CPU speed, that's not a problem. Clocking a SLOWER one is. With a separate crystal, you can even use a slow 881 with an fast XA. Even a slow (14MHz) 881 is lots faster than no math chip on float ops. –Redmond
#61109From: Joe BuckleyAug 1, 1993 7:50 PM
Redmond, Thanks for that information. I was certain that a slower FPU would need the seperate crystal, but was unsure if the a faster FPU needed its own as well. Now if I can find a cheap '882! 🙂 Joe
#61164From: R. Simonsen/MicroBoticsAug 2, 1993 7:10 PM
Joe: you can use a FASTER FPU at a slower speed without problem. Only the reverse situation is a problem (you should never overclock a math chip regardless of what any mfr might tell you in order to make his product sound faster in terms of MHz). –Redmond