| 摘要 |
PURPOSE:To display the state of a microprocessor by providing a circuit discriminating whether the microprocessor is being operated, or stopped by the instruction of a microprogram, or by an instruction from a hardware for constituting a device. CONSTITUTION:A microprocessor 1 stores an error and initial diagnostic information to a register 3 through a date bus 2, converts this information to a numeral or the alphabet, and displays it on a state display tube 4. When a signal for stopping the microprocessor 1 is inputted from a terminal A, and its running is stopped, a stop signal 7 and a signal 6 for showing a stop state are inputted to a discriminating circuit 5. Outputs 8 and 9 of the discriminating circuit 5 turn on the specified part of the state display tube 4. For instance, in case of displaying two characters ''00''-''FF'' by 8-bit, in case >=''80'' is displayed, it shows the instruction by a hardware, and in case of ''40''-''7F'', it shows the instruction by a program. |
