公开(公告)号：CA1231459A

公开(公告)日：1988-01-12

申请号：CA481733

申请日：1985-05-16

Applicant: IBM

Inventor： COOPER RONALD J ,  MARSICO MARIO A ,  MATLACK RICHARD C JR ,  PESCATORE JOHN C ,  SMITH ROBERT L JR

IPC: G06F11/00 ,  G06F11/10 ,  G06F11/22 ,  G06F11/267 ,  G06F11/273 ,  G06F13/00 ,  G06F13/12 ,  G06F13/26 ,  G06F13/28 ,  G06F13/32 ,  G06F13/364 ,  H04L5/22 ,  H04L29/00 ,  H04L29/02

Abstract: SCANNERLESS MESSAGE CONCENTRATOR AND COMMUNICATIONS MULTIPLEXER A communications concentrator and message multiplexer featuring direct access from the communications adapters to main memory via direct memory access means which eliminates the usual scanner or polling facility in a concentrator or multiplexer is described. A control microprocessor manages the allocation of memory, the conversion of message protocols and the servicing of interrupts to a plurality of port interface adapter microprocessors. The interface adapter microprocessors directly set up and control the DMA operation instead of having the DMA operation controlled by the control processor. One of the port adapters serves as a service adapter over a dedicated interface allowing a remote diagnostician access to internal registers in the control processor system, access to a dedicated read only storage for servicing, and logical interface to the main control processor for the purpose of entering instructions and directing functional operations to test each component of the system.