870646c@aucs.UUCP (Barry Comer) (04/20/89)
I am thinking of buying a 68020 board for my Amiga 2000, but I was wondering if the cache on the 68020 is normally active or does the programmer have to turn it on??? later Barry Comer 870646c@aucs.UUCP
bryce@cbmvax.UUCP (Bryce Nesbitt) (04/22/89)
In article <1835@aucs.UUCP> 870646c@aucs.UUCP (Barry Comer) writes: >...but I was wondering >if the cache on the 68020 is normally active or does the programmer >have to turn it on??? The 68020 instruction cache defaults to OFF at external reset (or power on). In the specific case of the Amiga OS, the Executive detects the 68020, and turns on the cache. Programmers may query the system for the CPU type, but generaly there is no need to. -Bryce Nesbitt, Commodore-Amiga, Inc. Note that the RESET *instruction* does not disable the cache, MMU or FPU. This can make a soft reboot just a bit trickier to write :-). -- |\_/| . ACK!, NAK!, EOT!, SOH! {O o} . Bryce Nesbitt, Commodore-Amiga, Inc. (") BIX: bnesbitt U USENET: cbmvax!bryce@uunet.uu.NET -or- rutgers!cbmvax!bryce Lawyers: America's untapped export market.
daveh@cbmvax.UUCP (Dave Haynie) (04/22/89)
in article <1835@aucs.UUCP>, 870646c@aucs.UUCP (Barry Comer) says: > I am thinking of buying a 68020 board for my Amiga 2000, but I was wondering > if the cache on the 68020 is normally active or does the programmer > have to turn it on??? The 68020 comes up with the cache turned off. The Amiga operating since release 1.2 will turn it on before any user interaction takes place. The SetCPU program will allow you to turn it off, but there should rarely if ever be a reason for that. > Barry Comer 870646c@aucs.UUCP -- Dave Haynie "The 32 Bit Guy" Commodore-Amiga "The Crew That Never Rests" {uunet|pyramid|rutgers}!cbmvax!daveh PLINK: D-DAVE H BIX: hazy Amiga -- It's not just a job, it's an obsession