| 摘要 |
PURPOSE:To shorten the delay time, by dividing plural data processors into plural groups of different priorities, providing a bus use request line and a use permission line with each group and having a daisy chain system in each group. CONSTITUTION:Bus use request signal lines RQ0-RQ3 and bus use permission signal lines GR0-GR3 are connected to a bus controller 1. Plural data processors 2-n are divided into plural groups for each group of devices of equal priority. Then data processors 2-4 belonging to the same group are connected to the same line RQ3. For instance, a bus use request signal is delivered from the processor 3 via the line RQ3. When the controller 1 gives permission, a permission signal is delivered to the line GR3 in a daisy chain system and then transmitted to the requester processor 3 from the processor 2. The processor 3 occupies the bus. As a result, the delay time for the permission signal is shortened. Thus it is possible to provide an idle slot. |
