| 摘要 |
PURPOSE:To simplify a structure of a host computer, by dividing a specification table showing the control contents into two, providing only an important part on the host computer, and executing its backup. CONSTITUTION:The part surrounded by a dotted line is related to the start control and is not backed up by a host computer. If an abnormal state occurs in a subroutine controller 3, a changeover switch SW3 is switched to the side 2, and an immediately previous valve opening signal is transferred to a subtracter 13 of the high rank computer. This subtracter 13 compares the transferred valve opening signal with a valve opening signal obtained from calculation, and supplies its difference to a code discriminating part 31. This discriminating part 31 supplies a rise or fall signal to a counter in an analog memory 6 in accordance with a code of the difference, and updates it counting value. Subsequently, the counting value is converted to an analog value through a D/A converter and is outputted as a valve opening signal. |
