TCDS(4) BSD Kernel Interfaces Manual TCDS(4)NAME
tcds -- TURBOchannel dual-channel SCSI adapters
SYNOPSIS
tcds* at tc? slot ? offset ?
DESCRIPTION
The tcds driver provides support for the DEC TURBOchannel PMAZ-DS, PMAZ-FS, PMAZB-AA and PMAZC-AA dual-channel SCSI adapters. Each channel
is driven by the asc(4) driver. The PMAZ-FS (Alpha onboard only) and PMAZC-AA (option board) provide two Fast Narrow SCSI busses, while the
PMAX-DS (Alpha onboard only) and PMAZB-AA only provide Narrow SCSI. For the onboard Alpha controllers, one bus is for internal devices and
one bus for external devices.
SEE ALSO asc(4)BSD February 6, 2002 BSD
Check Out this Related Man Page
IOASIC(4) BSD Kernel Interfaces Manual IOASIC(4)NAME
ioasic -- baseboard IO control ASIC for DEC TURBOchannel systems
SYNOPSIS
ioasic0 at tc? slot ? offset ?
DESCRIPTION
The ioasic driver provides support for the DEC proprietary IOCTL ASIC found on all DEC TURBOchannel machines with MIPS (DECstation 5000
series, excluding the 5000/200) and Alpha (3000-series) processors. On these machines (including the 5000/200), all baseboard devices should
be configured as children of the ioasic device.
The ioasic provides hardware DMA channels and interrupt support for several baseboard devices, including one asc SCSI device with a scat-
ter/gather DMA channel, an mc146818-compatible mcclock, an Am7930 audio device bba, one or two scc two-port serial devices, and a AMD 7990
LANCE le Ethernet interface.
The ioasic is also used for the floppy-disc drive and audio/ISDN hardware on the Personal DECstation and audio-equipped TURBOchannel Alphas,
where the ioasic hardware provides a scatter-gather DMA channel between the 16-bit device and the 32-bit tc DMA address space.
Support for scatter-gather DMA eliminates the need for additional copying. A baseboard asc SCSI adaptor attached to an ioasic will give
slightly better performance than its tc counterpart.
SEE ALSO asc(4), bba(4), intro(4), le(4), mcclock(4), scc(4), tc(4)HISTORY
The ioasic driver first appeared in NetBSD 1.1, derived from DECstation boot-time configuration code in 4.4BSD.
BUGS
The DECstation 5000/200 does not actually have an IOASIC chip, but for consistency it must be configured as if it did.
BSD September 12, 1996 BSD