DR32 Device Interconnect

The DR32 Device Interconnect (often given as the acronym DDI) was a high-performance parallel interface provided by early VAX computers. It provided a 32-bit-wide parallel data path, along with an 8-bit path for control. It used Direct Memory Access to transfer blocks of data to and from main memory at rates of up to 6.67 Mbytes per second.

The DR32 could be used to connect to high-speed customer equipment; alternatively, two could be used to connect two VAX systems to each other. The DR32 was provided by:

• DR780 High-Performance Channel Interface
• DR750 General Purpose Interface

Further reading

• VAX Hardware Handbook Volume 1 (EB-25949-46) - covers the DR32 in Chapter 11, pp. 11-93—11-101 (pp. 520-535 of the PDF)