On Monday 08 October 2001 10:51 am, Skip Gaede wrote:
I need help!
I upgraded my system to a new MLB and a faster CPU. With the new board, I can't read or write to my ZIP drive (under Linux). I have a SCSI system, with an Adaptec 78xx controller, an Adaptec RW CDROM (also ATAPI), and the ZIP drive.
Kernel: 2.4.10
Under ATAPI, I've checked only use SCSI emulation and under SCSI I've checked SCSI CDROM.
My board has both conventional ATA connectors and PROMISE ATA100 connectors. The CDROM is attached to the conventional primary controller as master and the ZIP is attached to the secondary controller as master.
The drives are being supported as ide-scsi devices. Parameters passed in at boot time include hda=scsi and hdc=scsi
Anyone have any ideas?
Folks, It's taken a while, and I actually learned a lot about device drivers and the ide device drivers in particular. To sum it up, there was a bug in both the ide-floppy and ide-scsi drivers, which I was able to fix. The problem, at least on my system, was that the Zip drive issued an interrupt stating it was ready to receive a packet command somewhere in the vicinity of 30 msec before it was ready to actually receive the packet. My initial fix was not elegant. It involved sitting in a wait loop inside an interrupt service routine. Gadi Oxman, the original author, pointed out the error of my ways, and suggested that I implement it using the timer queue in the ide driver. The original fix used 70% of the cpu waiting on the timer. The revised fix uses < 1%. Later, Skip