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![]() Every file should #include the headers containing the prototypes for it's global functions. Signed-off-by: Adrian Bunk <bunk@stusta.de> |
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compressor | ||
lowlevel | ||
zftape | ||
Kconfig | ||
Makefile | ||
README.PCI | ||
RELEASE-NOTES |
Some notes for ftape users with PCI motherboards: ================================================= The problem: ------------ There have been some problem reports from people using PCI-bus based systems getting overrun errors. I wasn't able to reproduce these until I ran ftape on a Intel Plato (Premiere PCI II) motherboard with bios version 1.00.08AX1. It turned out that if GAT (Guaranteed Access Timing) is enabled (?) ftape gets a lot of overrun errors. The problem disappears when disabling GAT in the bios. Note that Intel removed this setting (permanently disabled) from the 1.00.10AX1 bios ! It looks like that if GAT is enabled there are often large periods (greater than 120 us !??) on the ISA bus that the DMA controller cannot service the floppy disk controller. I cannot imagine this being acceptable in a decent PCI implementation. Maybe this is a `feature' of the chipset. I can only speculate why Intel choose to remove the option from the latest Bios... The lesson of this all is that there may be other motherboard implementations having the same of similar problems. If you experience a lot of overrun errors during a backup to tape, see if there is some setting in the Bios that may influence the bus timing. I judge this a hardware problem and not a limitation of ftape ;-) My DOS backup software seems to be suffering from the same problems and even refuses to run at 1 Mbps ! Ftape will reduce the data-rate from 1 Mbps to 500 Kbps if the number of overrun errors on a track exceeds a threshold. Possible solutions: ------------------- Some of the problems were solved by upgrading the (flash) bios. Other suggest that it has to do with the FDC being on the PCI bus, but that is not the case with the Intel Premiere II boards. [If upgrading the bios doesn't solve the problem you could try a floppy disk controller on the isa-bus]. Here is a list of systems and recommended BIOS settings: Intel Premiere PCI (Revenge): Bios version 1.00.09.AF2 is reported to work. Intel Premiere PCI II (Plato): Bios version 1.00.10.AX1 and version 11 beta are ok. If using version 1.00.08.AX1, GAT must be disabled ! ASUS PCI/I-SP3G: Preferred settings: ISA-GAT-mode : disabled DMA-linebuffer-mode : standard ISA-masterbuffer-mode : standard DELL Dimension XPS P90 Bios version A2 is reported to be broken, while bios version A5 works. You can get a flash bios upgrade from http://www.dell.com To see if you're having the GAT problem, try making a backup under DOS. If it's very slow and often repositions you're probably having this problem. --//-- LocalWords: ftape PCI bios GAT ISA DMA chipset Mbps Kbps FDC isa AF ok ASUS LocalWords: SP linebuffer masterbuffer XPS http www com