An auxiliary memory unit for use with electronic calculators which enables verification of a series of numeric data and function entries without requiring manual re-entry. Data and function signals generated by manual actuation of a calculator keyboard are sequentially stored in a storage device in the auxiliary memory unit during a first mode of operation, termed STORE.After a complete series of entries has been made, the stored signals are sequentially read out and displayed in the original order of entry during a second mode of operation, termed READ. The stored function signals are also read out so that the read out numeric data signals are processed by the calculator during READ. The unit further includes edit function circuitry for enabling erroneous data to be corrected by operation of the calculator keyboard, circuitry for providing automatic data alignment at the beginning of the READ operating, and circuitry for indication an incipient full condition for the auxiliary memory unit storage device during the STORE operation.