PURPOSE: To perform arithmetic processing for each input signal and to perform printing operation in an optional recording format by specifying the arithmetic processing and recording format for the input signal optionally with keys.

CONSTITUTION: When A/D conversion 28 is carried out in input processing and signals from a front push-button switch 6 and a flank switch 11 are inputted through a keyboard interface part 32, an arithmetic program corresponding to a function program is read out and an arithmetic processing part 29 performs arithmetic processing. Then, program generation processing is performed and a function program is generated on the basis of the switch signals. The result is stored in a memory part RAM 33. Further, the display process consisting of a display of flank program data by a flank display part 35 and a digital display of a front input signal is performed and then print data generated by the arithmetic processing part 29 is outputted to a thermal printing part 39 and printed. Then, arithmetic period waiting operation is performed and input processing is performed again in an arithmetic period.