Honeywell 6000 Series Reference Manual page 16

Link Adapter (LA)
The LA connects the DSC to the EUS as shown in Figure 2 -1 through 2 -4. Each LA has
two ports, providing the ability for the LA to be shared by two physical interface channels for
nonsimultaneous transfer of data between the EUS and the DSC. Channel switching is con-
trolled by the DSC rnicroprogranlS.
Disk Storage Control (DSC)
The DSC is a general purpose, register-to-register microinstruction processor
th~t
performs the control functions fOr the subsystem. The DSC accepts macro inst1"uctions from
the EUS and issues the necessary machine instructions to the DSU's via the DCA. The DSC
also obtains status from the DSU's and returns the appropriate status to the EUS. Four
ports are provided in the DSC for connecting as many as two LA's and two DCA's.
Disk Control Adapter(DCA)
The DCA connects the DSC to the DSU's through the Additional Drive Electronics
(ADE/ EDE) as shown in Figures 2 -1 th: .... ough Z -4. The DCA synchronizes, buffers, and
converts information to be transferred between the DSC and the DSU's. Information is
transferred by the DCA to or from only one DSU at a time. Two independent DCA's each
can transfer information to or from different DSU's simultaneously.
Disk Storage Unit (DSU)
The DSU is a disk pack drive capable of reading from or writing in bit serial form on
any of the tracks of a 19-recording surface, 411-track removable disk pack. To be inter-
changeable, all disk packs must be aligned with the same master alignment pack. Two
channels in the DSU permit the DSU to be connected to two DCA's for simultaneous data
transfer operations between the DSU and the EUS. DSU functional characteristics are
listed in Table 2 -1.
2 -4 DB37