Had a productive day refitting all the lamp lenses on P-Rack. The simulator ran well again following an initial problem with a WEETABIX card at power on, not a fault as such as the WEETABIX cards just needed pulling and re inserting. The simulator ran well apart from a couple of display (mains) glitches which always happen at lunch time. The reliability of the simulator is now so good we refitted the covers to the computer racks! Trying to develop a PeriBus simulator. Yet to be completed but the timing of the serial PeriBus L5 and L6 is done as is one of the L1/L4 lines. This will enable us to drive the I/O cards for stand-alone testing.