| 摘要 |
PURPOSE:To facilitate a function test for deciding whether or not the conversion result of an A/D converter incorporated in the microcomputer is within a range of guaranteed precision and shorten the test time by processing the majority of the function test by hardware. CONSTITUTION:This microcomputer is provided with an upper-limit value counter 5 and a lower-limit value counter 6 wherein the upper-limit value and lower- limit value of the guaranteed precision of the A/D converter 1 are set, a computing element 7 which compares the conversion result of the A/D converter 1 stored in a register 2 with the set values of the upper-limit value counter 5 and 1ower-limit value counter 6, and an interruption request flag 8 which requests an interruption of a CPU 4 unless the A/D conversion result is within the range of the guaranteed precision judging from the result of the operation by the computing element 7. |
