Electronic postage meter having a one time actuable operating program to

Abstract

In order to allow manufacturing complete freedom in testing and to insure that a customer receives an electronic postage meter or electronic parcel register preset to known values, the meter is operable to preset the internal registers in the accounting module when a serial number is locked in the unit. The dollar values in the ascending and descending registers, and the unit piece count may be preset to any pre-determined value only once during the life of the nonvolatile memory device associated with the accounting module in an electronic postage meter or electronic register. The serial number lock is modified to enable the internal register modification to be provided. To minimize any unauthorized abuse, by an external stimulus or by an internal failure, the serial number lock is stored before each register value is preset. The serial number lock is set after the preset to bar unauthorized entry into this sensitive routine. If a set lock is detected during any of the tests, a non-recoverable fatal error is set in meter/register. Operation of the unit is prevented if this fatal error condition is detected during the power-on sequence of the meter or register.