AHC(4) NetBSD Programmer's Manual AHC(4) NNAAMMEE aahhcc - Adaptec VL/EISA/PCI SCSI host adapter driver SSYYNNOOPPSSIISS For VL cards: aahhcc00 aatt iissaa?? ppoorrtt ?? iirrqq ?? For EISA cards: aahhcc** aatt eeiissaa?? sslloott ?? For PCI cards: aahhcc** aatt ppccii?? ddeevv ?? ffuunnccttiioonn ?? To enable tagged queueing: ooppttiioonnss AAHHCC__TTAAGGEENNAABBLLEE To enable SCB paging: ooppttiioonnss AAHHCC__SSCCBBPPAAGGIINNGG__EENNAABBLLEE For SCSI busses: ssccssiibbuuss** aatt aahhcc?? DDEESSCCRRIIPPTTIIOONN This driver provides access to the SCSI bus connected to an Adaptec 274x, 284x, 2940, 3940, or controllers based on the AIC7770, AIC7850, AIC7860, AIC7870, or AIC7880 host adapter chips. Features include support for twin and wide busses, ultra SCSI, two active commands at a time per non- tagged queueing target, tagged queuing, and SCB paging which allows up to 255 active commands on all adapters except those using AIC7770 chips pri- or to revision E. Tagged queueing is enabled with the ``AHC_TAGENABLE'' configuration option. SCB paging is enabled with the ``AHC_SCBPAGING_ENABLE'' configuration option. Per target configuration performed in the SCSI-Select menu, accesible at boot in non-EISA models or through an EISA configuration utility for EISA models, is honored by this driver with the stipulation that the BIOS must be enabled for EISA adaptors. This includes synchronous/asynchronous transfers, maximum synchronous negotiation rate, disconnection, and the host adapter's SCSI ID. Note that I/O addresses are determined automatically by the probe rou- tines, but care should be taken when using a 284x (VESA local bus controller) in an EISA system. Ensure that the jumpers setting the I/O area for the 284x match the EISA slot into which the card is inserted to prevent conflicts with other EISA cards. BBUUGGSS Some Quantum drives (at least the Empire 2100 and 1080s) will not run on an AIC7870 Rev B in synchronous mode at 10MHz. Controllers with this problem have a 42 MHz clock crystal on them and run slightly above 10MHz, causing the drive much confusion. Setting a maximum synchronous negotia- tion rate of 8MHz in the SCSI-Select utility will allow normal function. SCSI residual handling is not complete on NetBSD version of this driver. SSEEEE AALLSSOO aha(4), ahb(4), cd(4), sd(4), st(4) AAUUTTHHOORR The aahhcc driver was written by Justin Gibbs. The AIC7xxx sequencer-code assembler was written by John Aycock. NetBSD porting is done by Stefan Grefen, Charles M. Hannum, Michael Graff, Jason R. Thorpe, Pete Bentley and Noriyuki Soda. HHIISSTTOORRYY The aahhcc driver appeared in FreeBSD 2.1 and NetBSD 1.1. NetBSD April 20, 1996 2