GSC(4)                OpenBSD Programmer's Manual (HPPA)                GSC(4)

NAME
     gsc - introduction to HP 9000/700 GSC bus support

SYNOPSIS
     gsc* at lasi?
     gsc* at asp?
     gsc* at wax?

DESCRIPTION
     The General System Connect (GSC) bus is the core I/O bus for all HP
     9000/700 workstations.  All I/O subsystems connect to this bus.  The de-
     vices can be either on separate chips, expansion cards or on an integrat-
     ed megacell, like the LASI MBA.

     The GSC bus is a 32-bit wide, address and data multiplexed bus.  In its
     "standard" implementation it has a maximum throughput of 160MB/s, the
     "2x" implementation reaches up to 250MB/s.  Some HPPA CPUs directly at-
     tach to this bus, namely the PA7100LC and PA7300LC.

     As for the expansion cards, there are different form-factors, depending
     on bus-speed (standard or 2x) and specific models.  The standard formfac-
     tor is the "EISA form-factor"; cards that look like typical EISA cards
     with a different connector (100-pin female EBBL).  The Series 712 have
     their own special type of GSC expansion cards, called the "GIO form-fac-
     tor", which is quite small and mostly has only one VLSI chip on it (in
     most cases LASI/WAX).  Newer systems sometimes feature the "HSC formfac-
     tor", which is a 1U-VME card-like expansion card with a 100-pin male
     pin+socket connector.  Mixing cards with different speeds is supported
     but downgrades the performance of the whole I/O-subsystem.

     OpenBSD provides support for the following devices:

           com(4)        serial communications interface
           gsckbc(4)     PC-style keyboard controller
           harmony(4)    CS4215/AD1849 audio
           hil(4)        introduction to HP-HIL support
           ie(4)         Intel i82596 Ethernet device
           lpt(4)        parallel port driver
           oosiop(4)     Symbios/NCR 53C700 SCSI I/O Processor
           osiop(4)      Symbios/NCR 53C710 SCSI I/O Processor

     Some of these GSC devices also have PCI, EISA, or ISA equivalents.  These
     are listed in pci(4), eisa(4), or isa(4).

SEE ALSO
     asp(4), cpu(4), intro(4), lasi(4), wax(4)

HISTORY
     The gsc driver appeared in OpenBSD 2.6.

OpenBSD 4.7                      June 21, 2007                               1
