| 摘要 |
PURPOSE:To obtain a system which requires no special circuit and also does not stop an operation of a device in order to test a part of a circuit by constituting a titled system so that an input/output instruction can be executed from both a processing processor and a service processor. CONSTITUTION:The titled system is constituted so that an equal input/output instruction can be executed for an input/output adaptor from both a processing processor and a service processor. For instance, in a processing processor P, in case an instruction read out of an MEM is an IO instruction, an ADP is sent out onto a C bus from the P, data IOA for designating its IO instruction is sent out onto an A/D bus, and a signal PA for showing a fact that its sending-out origin is P is sent out to a P/S bus. Subsequently, each ADP1-(n) decodes the IOA, and in case its contents show itself, a kind of its IO instruction is discriminated, and input data IOD is sent out to the A/D bus. In a service processor SVP, a signal SA is sent out of an SA generating circuit by writing data corresponding to said IOA in a register RI. |
