An active-matrix display device employs current-programmed-type pixel circuits and performs the writing data to each of pixels on a line-by-line basis. The battery holder may include a cradle and a resilient retention strap configured to be deflectable between relaxed and deflected positions. The sender and the recipient are both configured to determine a check sum based on a plurality of corresponding data frames that are sent to and, respectively, received from the at least one transmission line.