Photocopier costing calculator - has counter circuits to prevent user making small number of copies while being charged at lower rate appropriate to large number of copies

摘要

The photocopier has a copy control which is set by the user to the number required, and that number is used to address a memory, which adds an appropriate number of count pulses to the total for each copy. To prevent fraud, if the user programmes a large number of copies and stops the machine early in the cycle. The two counters are used. One counter is preset to the charge factor for a programmed cycle, and the other counts the charge per copy during the cycle. If the totals at the end of the cycle are identical, the first counter figure is added to the totaliser. If not, the difference between them is used to calculate a new factor appropriate to the number of copies.