[9fans] Re: etherelnk3.c

[jim mckie jmk@plan9.bell-labs.com]

	>But how do those controllers compare to the Qlogic board or
	>the Adaptec 294x?  The QLogic board has two processors like
	>the 154x and you only get one interrupt per SCSI command.
	>(like the 174x. you can get many completed per interrupt on the
	>154x.) The 2940 gives interrupts as targets disconnect/reconnect!
	>The host processor has to almost manage the SCSI bus directly.
	>A 154x will even retry a command to a BUSY LUN for you without
	>issuing another interrupt.

the buslogic, ncr and dpt controllers do everything the 154x does,
and more. ngr has answered about the ncr controllers, and i've used
them without problem. the buslogic controllers are available in isa,
eisa and pci, narrow/wide/differential. they are software compatible
with the 154x but the eisa and pci have a 32-bit extended mode. we
use one driver for all 154x and buslogic cards, the only thing it
has to deal with differently on configuration is if it's a 1542c/cf
which has the mbox-lockout 'feature'.