Very Computer

Hello all,

I get serious errors when I use the floppy on my linux pc with a Buslogic
445S VLB scsi controller (the on-board tape is disabled).  See below for
more details of my setup.
With linux 1.1.25 I had complete crashes in some cases that I accessed the
floppy. This was a complete system lock with no panic messages.

Now with 1.1.42 I run an iozone 20 (scsi disk) and at the same time I try
floppy read operations. The problem manifests itself with messages:
floppy: dma problem?
40,10, 0, 5, 0,11, 2,
floppy: dma problem?
40,10, 0, 7, 0, a, 2,
...
The motor jumps with funny noises.
After this one of the following may happen:
1) operation is normal
2) 'illegal command' messages on most operations
3) complete lockup (without any panic message)

Back in 1.1.25 the problem did not appear before I used the Buslogic
scsi controller on. I wonder if the same problem occurs with other
scsi controllers.

This is a rather * problem. Could you cast some light on this?
Could it be connected with the BIOS settings (bus timing etc.)?

Thanks,
Angelo

Details of h/w, setup: (bus_type is E and dma is 0 on buslogic stratup):

Some output from dmesg:
BusLogic SCSI: Inquiry Bytes: 41 41 33 33
Configuring BusLogic EISA/VESA HA at port 0x330, IRQ 11, ID 7
BusLogic SCSI: interrupt received, but no mail
scsi0 : BusLogic
scsi : 1 hosts.
  Vendor: COMPAQ    Model: ST12550N          Rev: 3215
  Type:   Direct-Access                      ANSI SCSI revision: 02
Detected scsi disk sda at scsi0, id 0, lun 0
  Vendor: WANGTEK   Model: 5525ES SCSI CPQ1  Rev: 6G15
  Type:   Sequential-Access                  ANSI SCSI revision: 01
Detected scsi tape st0 at scsi0, id 4, lun 0
scsi : detected 1 SCSI tape 1 SCSI disk total.
Memory: 12072k/13312k available (564k kernel code, 384k reserved, 292k data)
This processor honours the WP bit even when in supervisor mode. Good.
Floppy drive(s): fd0 is 1.44M
FDC 0 is a 8272A
Partition check:
  sda: sda1 sda2 sda3 sda4 < sda5 sda6 sda7 sda8 >
  hda: WDC AC2340, 325MB w/127KB Cache, CHS=1010/12/55, MaxMult=16
  hda: hda1 hda2
--
#include <standard.disclaimer.h>
 Angelo Haritsis, Applied Systems Section
 s-mail: Dpt of Computing,Imperial College, 180 Queen's Gate, London SW7 2BZ, UK

I had a similar problem with my BT445S. When I was reading large
amounts of data from a floppy (tar or dd), while simultaniously
writing to or reading from the hard disk, the BusLogic would
lock up during the hard disk access with no error messages. The
LED on the controller remained on and the system was dead. It
made no difference whether I used the floppy controller on the
BusLogic or the floppy controller on a multi I/O card.

I had some other problems with my new system as well, and I got
a replacement motherboard. With the new motherboard the floppy
problem also disappeared! It seems that not every VLB adapter
card works in every VLB motherboard.

--> This is a rather * problem. Could you cast some light on this?
--> Could it be connected with the BIOS settings (bus timing etc.)?

The ISA bus speed should be 8 MHz or slightly larger. I use
(and used on the previous board) 33 MHz/4 = 8.25 MHz. Perhaps
it is some kind of timing problem. It might also be a firmware
problem of the BT445S. I have a board revision C, firmware
version 3.35, BIOS version 4.70.

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