  Seeking Device Control I/O? 
 The Question is:
 
I need to control some simple HW with a 4-bit parallel DC output signal. This
 is easy enough on an PC's parallel port... but how can I do it on a DS10 with
 V7.3 ??
Maybe I can use $QIOs to the printer driver?
Or maybe I'll end up having to write my own driver.... but then where does one
 find HW programming info for this Pport on an alpha?
(or is it same as PC?)
Thanks.
 The Answer is :
 
  SYS$EXAMPLES:LRDRIVER.* is the source code for a parallel port
  device driver, and can (obviously) be customized to meet local
  requirements within the limitations of the available hardware.
 
  Device control options can and do vary; the standard parallel
  port driver does not particularly over this control.  The serial
  terminal driver can control modem signals via $qio[w], however.
 
  Commercial options include packages such as the BASEstar
  environment, and customized drivers for specific communications
  and control hardware.
 
  The Device Driver manual available from Digital Press may be
  of some interest, as well.  This book presents details on
  writing OpenVMS Device Drivers in C.
 
 Answer written or last revised on  20-MAR-2004 
