ken@HAMLET.CALTECH.EDU (02/06/86)
All of the DIGITAL literature I can find about HSC50s says that each disk data channel (-YA) supports 4 drives. The labels on the chassis of the HSC50 seem to indicate that each column of 4 ports on the back belongs to one disk data channel. The problem is that we have two of these data channels and only six working ports. The #3 (lowest) port on each data channel is dead, and our FE is stumped. We are considering purchasing some more RA81s and want to know if we can accomodate them. The HSC50 has the following cards: 1 L0100 REV D1 CI PORT LINK 1 L0109 REV E2 CI PORT BUFFER 1 L0107 REV C1 CI PORT PROCESSOR 2 L0108-YA REV C6/C6 DISK DATA CHANNEL (Slot 8 and Slot 4) 1 L0106-AB REV C1 MEMORY 1 L0105 REV E1 I/O CONTROLLER PROC as it was installed by DIGITAL during November 1984. We are currently running V250 of the microcode, but this problem did exist under V110. Any ideas? Also, does anyone know if there is a performance benefit from balancing the load between the disk data channels? Ken Adelman Caltech