From: system@SendSpamHere.ORG Sent: Thursday, July 05, 2001 10:19 AM To: Info-VAX@Mvb.Saic.Com Subject: Re: Writing to OPA0: from a device driver In article , koehler@encompasserve.org (Bob Koehler) writes: >In article , Simon Clubley writes: >> >> What are the various methods used by VMS device drivers to write (for example, >> debugging text) to the system console and which method do people prefer ? > >Generally they don't. It's somewhat difficult in any device driver to >write to any device other than the one being controlled. > >I've got device drivers that use the OPCOM mailbox, they haven't >successfully sent out a message in years. I haven't bothered debugging >this because the messages they did send out are useless. > >Writing the the system error log works as documented, and is quite >helpfull in deciphering device errors, sometimes due to the device >getting into a state the driver writer didn't expect. > >XDELTA is my primary debugging tool for drivers (mostly on VAXen), but >if you have two Alphas, I think there's a better debugger that runs >across the network from a host to a target. > >You can also log traces of things in buffers you add to the UCB. This >is helpfull when you can't stop for a breakpoint. > >It is possibly to construct an IRP and queue it to OPA0, but it's not >trivial. > >---------------------------------------------------------------------- >Bob Koehler | Computer Sciences Corporation >NASA GSFC Flight Software | Federal Sector, Civil Group > | please remove ".aspm" when replying I use IOC$BROADCAST and/or IOC$CONBRDCST extensively for outputting messages. You need to observe IPL requirements so you might not be able to invoke these routinese everywhere you might wish. In general, you can use these as you'd like at fork IPL. -- VAXman- OpenVMS APE certification number: AAA-0001 VAXman(at)TMESIS(dot)COM "And of course, I'm a genius, so people are naturally drawn to my fiery intellect. Their admiration overwhelms their envy!" -- Calvin & Hobbes