AT&T 3B2/300 Technical Reference Manual page 385

FUNCTIONAL D E S C R I P T I O N - - - - - - - - - - - - - - - - - - - - - - - - - - -
Direct Memory Access Subsystem
Subsystem Structure.
Figure 3-38 is a high-level functional block diagram of the Direct Memory
Access (OMA) Subsystem. The OMA Subsystem includes the following:
• Page Registers
• Floppy Control Register
• Floppy Disk Controller
• Floppy Controller Data Separator
• Direct Memory Access Controller
• Dual Universal Asynchronous Receiver/Transmitter.
Each of these functional areas is described in the following paragraphs.
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