Browse Prior Art Database

High-Speed Real-Time Resource Arbitrer

IP.com Disclosure Number: IPCOM000116016D
Original Publication Date: 1995-Jul-01
Included in the Prior Art Database: 2005-Mar-30
Document File: 4 page(s) / 70K

Publishing Venue

IBM

Related People

Blanc, A: AUTHOR [+3]

Abstract

Disclosed is a method for solving the access problem to a resource-sharing, by some devices with the same level of priority, the most quickly without scanning.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 75% of the total text.

High-Speed Real-Time Resource Arbitrer

      Disclosed is a method for solving the access problem to a
resource-sharing, by some devices with the same level of priority,
the most quickly without scanning.

RULES TO FOLLOW
  o  Acknowledgent in the arrival order of the requests.
  o  If simultaneous requests arrive, acknowledgments given with a
      fixed priority order.

IMPLEMENTATION PRINCIPLE - When a request REQi or more REQj, REQk...
arrive, a pulse Change_Up (CHG_UP) is generated.  This pulse is used
to increment the counter CTRa that presents the arrival order of the
requests (modulo n).

      For each acknowledgment (ACKi, i=1 to n), the counter CTRb,
that presents the order of acknowledgment (modulo n), is incremented.

      The difference between CTRb and CTRa gives the length of
pending request queue.  This value (REQ_POS) indicates the request
position in a wait-queue.  If several requests arrive in the same
time, the same value is affected to each request.

      For each request corresponds a Request_Counter (CTRi, i=1 to
n), loaded, when the REQi arrive, with the value REQ_POS.

      When one or more CTRi arrive at zero, the corresponding
requests are ready to be acknowledged if it is always present (GATE).
Then they are taken with a priority order by the priority encoder.
The successive acknowledges appear at the decoder outputs.

      When the priority encoder indicate the value '0'X, a pulse
Last_Acknowledge (LAST_ACK...