Based on kernel version 4.0. Page generated on 2015-04-14 21:26 EST.
1 README file for the Linux DTC3180/3280 scsi driver. 2 by Ray Van Tassle (firstname.lastname@example.org) March 1996 3 Based on the generic & core NCR5380 code by Drew Eckhard 4 5 SCSI device driver for the DTC 3180/3280. 6 Data Technology Corp---a division of Qume. 7 8 The 3280 has a standard floppy interface. 9 10 The 3180 does not. Otherwise, they are identical. 11 12 The DTC3x80 does not support DMA but it does have Pseudo-DMA which is 13 supported by the driver. 14 15 Its DTC406 scsi chip is supposedly compatible with the NCR 53C400. 16 It is memory mapped, uses an IRQ, but no dma or io-port. There is 17 internal DMA, between SCSI bus and an on-chip 128-byte buffer. Double 18 buffering is done automagically by the chip. Data is transferred 19 between the on-chip buffer and CPU/RAM via memory moves. 20 21 The driver detects the possible memory addresses (jumper selectable): 22 CC00, DC00, C800, and D800 23 The possible IRQ's (jumper selectable) are: 24 IRQ 10, 11, 12, 15 25 Parity is supported by the chip, but not by this driver. 26 Information can be obtained from /proc/scsi/dtc3c80/N. 27 28 Note on interrupts: 29 30 The documentation says that it can be set to interrupt whenever the 31 on-chip buffer needs CPU attention. I couldn't get this to work. So 32 the driver polls for data-ready in the pseudo-DMA transfer routine. 33 The interrupt support routines in the NCR3280.c core modules handle 34 scsi disconnect/reconnect, and this (mostly) works. However..... I 35 have tested it with 4 totally different hard drives (both SCSI-1 and 36 SCSI-2), and one CDROM drive. Interrupts works great for all but one 37 specific hard drive. For this one, the driver will eventually hang in 38 the transfer state. I have tested with: "dd bs=4k count=2k 39 of=/dev/null if=/dev/sdb". It reads ok for a while, then hangs. 40 After beating my head against this for a couple of weeks, getting 41 nowhere, I give up. So.....This driver does NOT use interrupts, even 42 if you have the card jumpered to an IRQ. Probably nobody will ever 43 care.