Embedded Technologies, Inc.

8237 DMA Controller

Description

8237 DMA Controller is a peripheral core for microprocessor systems. It controls data transfer between the main memory and the external systems with limited CPU intervention.

Product Specifications
  • 24-bit length address register
  • 16-bit length count register
  • 4 independent DMA channels
  • 4 clock / 1 bus cycle
  • Byte transfer / word transfer selectable
  • Supports three transfer modes (Single, Demand, Block)
  • DMA request Maskable on an individual channel basis
  • Software DMA request in uPD1037 mode
  • Auto initialization function
  • Two kinds of channel priority order (Fixed & Rotating)
  • Cascading capability

Highlights

  • Compatible with 8237 and uPD71071
  • Controller can improve the system performanceby allowing external devices to transfer data directly to or from systemmemory
  • Multi-mode programmability allows the user to select from three different transfer modes