CompuServe Thread

A2386 vs A2620 ???

5 messages in this thread
#104637From: Charles F. CoatsJun 23, 1993 7:51 PM
I added a used A2620 card with 68881 and 4MB. The dealer who sold it to me got it as a trade-in on an 030 card. I didn't get any docs or software with it. (Seemed like a good deal at the time.) Unfortunately, my A2386 card is now unavailable. I keep getting a cannot-load, or cannot-open, janus.library error when I try to use PCprefs or PCwindow. I re-installed the bridgeboard software three times. Neither enforcer nor CPU seemed to control the problem. I get the impression a ROM on the A2620 card is grabbing the system on boot-up and preventing NODATACACHE from taking effect. (Does OS2.1 require new ROM's for the A2620 card?) I've just added parallel/serial I/O, Paradise Accelerated VGA, MS/DOS 6.0, and Geos2.0 (recommended BTW). I don't want to have to choose between the A2386 and the A2620. I have the usual college faculty financial blues, and can't justify much more in upgrades. And the IBM compatability is pretty much mandatory! Any advice and information would be appreciated. Thanx. C F Coats –> via AutoPilot
#104736From: Steven D. KapplinJun 24, 1993 2:10 PM
Your problem is simply this: If you have any 16 bit RAM installed, you must be sure that you have NOT MORE than 7.5 meg of total RAM including the 4 meg on the accelerator. That accelerator does not map its 32 bit RAM out of autoconfig space, so you cannot have more than 7.5 meg of total RAM. If you have any 16 bit RAM disable some of it. You may not be able to disable 16 bit ram in less than 2 meg increments, which will reduce your total fast ram to 6 meg. You don't need to worry about the data cache on the 2620. The 020 only has an instruction cache, so that shouldn't be a problem. However, judging from your message, I would bet you have too much fast ram for the BB to run.
#104991From: Charles F. CoatsJun 26, 1993 12:15 AM
Steven, Yes, that was it! Thanks. I disabled 2MB on the 16-bit card, and the BB ran fine. Some areas of the campus (Clone-Zones and Mac-Fanats) have been telling the students what they can't do. Now I'm back to demonstrating what they Can Do (pun intended). C F Coats –> via AutoPilot C F Coats –> via AutoPilot
#105033From: Steven D. KapplinJun 26, 1993 11:26 AM
C F, Glad you got it working. It's rather unfortunate that CBM doesn't make any mention of the autoconfig requirement for the BB to work. I think they must assume that no one has 16 bit RAM or older accelerators which cannot map ram outside of the autoconfig space. They also conveniently have forgotten to include a mention of the need to run Enforcer or CPU nodatacache when the BB runs. These two areas seem to have created a lot of problems for people who are relatively new to the Amiga or haven't the hardware expertise. I guess they think that only dealers will do the installations.
#104806From: Greg GivlerJun 24, 1993 11:20 PM
How much total memory do you have. If you have more than 8 megs that is your problem. The bridgeboard needs at least a 512K of autoconfig space so if you have a machine with more than 8 megs you have to get it down to at least 7 some how, the general rule of thumb is that you have a bridgeboard and 6 megs of memory. Greg Greg Givler – CBMSER Sysop "By the way, don't eat the figs", Lydia, 'I Claudius'