wallen (09/01/82)
We have a Plessey dz11 which had been running happily in a VAX 11/780 for 2 years or so. We have recently moved it to a VAX 11/750, and (you guessed it!) the sucker doesn't work. Specifically, it's transmitter section gets wedged. Once one line is stuck, they all are--it will never transmit again until a reboot or serious register diddling is done (Master reset of the beast). The receiver portion seems okay, as evidenced by the fact that attempts to login on other lines on the same dz wide up posting their transmitter enable bits in the transmitter enable register. It happens "after a while" running at 1200 baud on a single line. It wedges quite quickly at 9600. To me, it smacks of a bus timing problem on the dz, like the dz can't get in because a large disk transfer (or ?) and then just sits on its hands. When talking to Plessey, "Oh yeah! The board is over a year old, ah you need the following mod". When we got the instructions for the mod, you guessed right again!, it was already installed. Questions: has anyone had this problem before (there is an 11/750 next door with EXACTLY the same problem with their Plessey dz)? How to fix it--sending back will likely yield nothing as Plessey almost certainly doesn't have a 750? Will DEC DZ diagnostics show up the problem (do diagnostics ever?)? Moral: Some DEC compatables are more compatable than others. What I would really like to do with more had best refrained to ug.jokes. Help or crying towels to: Mark Wallen ucbvax!sdcsvax!wallen ucbvax!sdcsvax!sdcsl:wallen wallen@nprdc