clemon@lemsys.UUCP (Craig Lemon) (10/10/90)
This may have been discussed before but in the process of switching
feeds a while ago I may have missed it... I have a B2000 REV 4.2 (yech!),
When I get the SuperFat AGNUS, what jumpers do I have to change to activate
the new CHIP RAM. What about a 2Meg Agnus? While we're at it, what do all
the jumpers do, worse yet, where are they. I can't say I remember seeing a
rather large bank of jumpers anywhere. I have always liked to install and
prep my own expansion equipment so I know how it works, where it goes and
what brand it is etc... I had no choice when I got floppy #2 and never saw
what jumpers they changed to activate it. Any jumper data is appreciated.
As always!
--
Craig Lemon - Kitchener, Ontario. Amiga B2000/10--2400 bps--AmigaUUCP 1.03D
clemon@lemsys.UUCP or lemsys!clemon@xenitec.on.ca
....!{uunet}!watmath!xenitec!lemsys!clemondaveh@cbmvax.commodore.com (Dave Haynie) (10/11/90)
In article <3198.655534613@lemsys.UUCP> clemon@lemsys.UUCP (Craig Lemon) writes: > This may have been discussed before but in the process of switching >feeds a while ago I may have missed it... I have a B2000. When I get the >SuperFat AGNUS, what jumpers do I have to change to activate the new CHIP RAM. You move the J101 jumper, a two way jumper, to its alternate position. You then remover or cut, depending on the jumper style, J500. You'll find J101 near the Agnus chip and the power connector, the J500 jumper is below the GARY chip. >What about a 2Meg Agnus? The A2000b doesn't support the 2Meg Agnus. You don't see any room for another meg of Chip RAM on that motherboard, eh? >While we're at it, what do all the jumpers do, worse yet, where are they. J101 changes an address line to Agnus, so that she addresses the second memory bank at $00080000 rather than $00C00000. The J500 jumper turns off the decoding of $00C00000 as memory, so that they system software doesn't get confused and think that there's still memory up there. >I can't say I remember seeing a rather large bank of jumpers anywhere. There isn't any large bank of jumpers. There are only a few jumpers on the 2000 PCB, and they're located for reasons of layout quality rather than ergonomics. >I had no choice when I got floppy #2 and never saw what jumpers they changed >to activate it. Any jumper data is appreciated. As always! The second A2000 floppy is enabled by closing J301. The doesn't really do anything to the floppy, it simply enables the Amiga-special floppy type code generator, so that when the OS interrogates that floppy, it responds as a normal 3.5" 880K floppy, and it'll get automounted. Without the jumper, you would need to write a mountlist entry for the floppy and then manually Mount it. > Craig Lemon - Kitchener, Ontario. Amiga B2000/10--2400 bps--AmigaUUCP 1.03D -- Dave Haynie Commodore-Amiga (Amiga 3000) "The Crew That Never Rests" {uunet|pyramid|rutgers}!cbmvax!daveh PLINK: hazy BIX: hazy Standing on the shoulders of giants leaves me cold -REM