| 摘要 |
PURPOSE:To attain the function test of an ALU and the test of a microinstruction by obtaining the ANDs between a test mode signal and each microcomputer which controls a register and an input/output gate of a RAM and carrying out an instruction equivalent to a port input/output instruction based on those obtained AND outputs. CONSTITUTION:The ANDs are obtained between a test mode signal and each microcode which controls the registers 5 to 7 and an input/output gate G of a RAM 1. Based on these AND outputs, an instruction equivalent to a port output instruction is carried out. That is, the output gates and the output port gates of the registers 5 to 7 and the RAM 1 are controlled when an instruction is carried out to store and transfer data to the registers 5 to 7 and the RAM 1. As a result, an input instruction can be tested to an optional block of a microcomputer without carrying out a test program for the external output. |
