Introduction

The Submillimeter Array computers make use of fiber-optic reflective memory from VME Microsystems International Corporation, part number VMIVME-5576. These VME boards allow 256K of RAM to be shared between the array's central computer and the antenna computers. Information written to reflective memory on one end appears on the other end within . They also provide the capability for a board to cause an interrupt to be generated on the VME bus of another board. This feature is used to provide notification between computers when reflective memory contents are changed.

In the final configuration of the SMA, with 8 antennas plus the JCMT and CSO, there will be 10 pairs of reflective memory cards. Each will connect the central computer to one of the 10 antennas.