| 摘要 |
PURPOSE:To reduce the required chip area and to enable manufacture at low cost, by using a part of data memory of a microcomputer to count the output of an A/D converter. CONSTITUTION:When an A/D conversion start signal is externally given, a pulse output circuit 23 outputs the number of pulses according to an input analog voltage. When this pulse is detected, a control circuit 24 temporarily interferes the execution of the next instruction after the end of instruction during execution at present. Instead, when the instruction to make count operation of output pulse is executed, the data in an address area for count in a data memory 14 is advanced by one. As a result, an analog input voltage in digital conversion is stored in the data memory 14. |
