Talk:Massbus

If "Multiple devices of different types could transmit data over the shared data path. However, this was never supported by DEC operating systems." means what I think it mean, ie. having both tape drives and disks (for example) on the same massbus controller, then the claim is incorrect. RSX-11M+ supports something called "Mixed Massbus configuration", which means exactly that. You can put any kind of different types of devices on the same massbus. —Preceding unsigned comment added by 74.125.57.36 (talk) 16:08, 30 August 2010 (UTC)

The article says "Static dual port is also provided to permit failover or manual switching of storage devices to another CPU.". This is not what the dual porting in Massbus was for, or how it worked. Yes, you could manually lock a device to one port, and manually switch it over to another, but normally you left it in the state where both ports were usable. This was used by the KL-10 for example, where both the PDP-10 and the front-end PDP-11 are connected to a shared RP06, which both use at the same time, through their own controller. It is also used by RSX-11M+ where you can have a disk connected to two controllers to have higher performance. If one controller is busy with some other transfer, the disk can still be reached on the other controller. So the disk switches ports dynamically all the time. /bqt@softjar.se 178.82.219.170 (talk) 13:32, 9 February 2016 (UTC)