Date: Tue, 2 May 1995 13:01:25 +0200 From: se@MI.Uni-Koeln.DE (Stefan Esser) To: Nate Williams <nate@trout.sri.MT.net> Subject: Re: NCR 53C700 Message-ID: <199505021101.AA01730@FileServ1.MI.Uni-Koeln.DE> In-Reply-To: Nate Williams <nate@trout.sri.MT.net> "Re: NCR 53C700" (May 1, 16:52)
next in thread | previous in thread | raw e-mail | index | archive | help
On May 1, 16:52, Nate Williams wrote: } Subject: Re: NCR 53C700 } } The reason I said it was a completely different beast was because a } friend of mine tried porting his 53c7xx driver and it didn't work on the } new cards due to functionality changes. The addition of bus-mastering } and other new features made (in his mind) the older chipset obsolete. Hmm, seems our opinions don't differ that much. You concentrate on the differences; I looked at the similarities ... :) In fact, the bus interface, lack of clear rules (i.e. flexibility) of register access methods and need to be integrated into a system's DMA environment make writing a generic 53c7xx driver a lot harder than doing the same thing for the 53c8xx, which has all these fixed (by having it integrated on the controller chip). By using the SDMS BIOS extension to drive the NCR chips, a driver could be written to support both (Drew Eckhard did this for Linux). But at a severe penalty in transfer speed and CPU load ! I also consider the 53c7xx chip set obsolete in the PC environment, but it has been used on S-Bus cards and other non-PCI cards, AFAIK. STefan
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199505021101.AA01730>