Hearing aid programming interface and method

A method of programming a programmable hearing aid is disclosed. The programmable hearing aid has a serial data interface for receiving data transmissions, a decoder for decoding data transmissicns, a program memory which stores program data values received via the serial interface, and read control logic that transmits the program data stored in the program memory when the decoder detects the receipt of a predefined read signal. Programming begins with the sending a set of program data values to the programmable hearing aid, preceded by a predefined write signal. The hearing aid automatically mutes or inhibits its operation upon receiving the write signal. A first checksum value corresponding to the program data values sent to the programmable hearing aid is calculated. Next, the data stored in the hearing aid is checked by sending a predefined read signal to the hearing aid, causing the hearing aid to transmitting the program data stored in its program memory. A second checksum value corresponding to the program data transmitted by the hearing aid is calculated and compared with the first checksum value. If the first and seccnd checksum values do not match an error signal is generated and the hearing aid remains muted. If the checksum values do match, an unlock signal is sent to the hearing aid, causing the hearing aid to resume normal operation.