This directory contains 'pti.c' a loadable device driver for SparcStations
with a Performance Technologies SBS915 SBus->VME card. 

This driver provides three 'sub-devices' (specified through the minor device
number).  '0' is for control of the SBus->VME card, '1' is for control of a
XYCOM XVME 203 clock card (in the external VME chassis), and '2' is for control
of a XYCOM XVME 240 parallel card (in the external VME chassis).

As such, this device driver replaces the 'xyclk.c' and 'xyd.c' device drivers
that RCI would normally require you to build into the kernel.

To install the device driver, build 'pti.o', and run 'pti.INSTALL' on the
appropriate machine.  For use with RCCL/RCI, you'll also need to make (by
hand) a few symbolic links.  (link /dev/rciclk to /dev/pti_clk, and link 
/dev/xydRCI0 to /dev/pti_par)

Also included is 'drvtest', a program which tests the device driver's ability
to control the clock card, and 'vmereset', a program which will reset the 
external VME bus, should that be necessary.

It should be noted that the device driver is not especially bullet-proof.
If the external VME chassis is turned off, or reset, the SparcStation will 
probably crash as well.  However, depending on how righteous you feel at the
moment, it can be argued that this is perfectly reasonable behavior.

John Bradley  -  bradley@cis.upenn.edu

