An address translator includes an SIP message detecting function. The invention includes a defect solution component and a defect alert component. A component held by one chamber is mixed with a component of the corresponding other chamber by transfer into the other chamber. A variance combining circuit combines the individual power measurements to provide a variance for the individual shift registers. The biasing-force control mechanism operates to ensure, when the platen is mounted to the frame, a required contact pressure between the thermal head and the platen under the biasing force, and to prevent, when the platen is removed from the frame, the thermal head from being deformed due to the biasing force. A sum of page counts between hard breaks is calculated up to the identified hard break.