| 摘要 |
<p>PURPOSE:To debug a ROM easily in a high speed, by updating contents of a program counter by a processing mode fixing means. CONSTITUTION:Contents in an address designated by a program counter 10 are outputted to a bus 4 from a ROM where instructions are stored. In the normal processing mode, a TEST signal 12 is fixed. As the result, contents outputted from the ROM 1 are taken into an instruction register 8 through an AND gate 6 and a transfer gate 7. A control part 9 decodes this taken-in instruction to generate a group 13 of determined various control signals. Consequently, the control part 9 has a decoder circuit, an encoder circuit, etc., and the generated control signal group 13 is led to a logical processing part, control gates, registers, etc., to execute processings based on the instruction.</p> |
