| 摘要 |
PROBLEM TO BE SOLVED: To reduce the number of signal lines to be used for transmitting serial data when transmitting these data with serial signals. SOLUTION: A memory card 20 is provided with a memory 21, a register 22, a card side serial interface circuit 23 and a card side controller 24. During a period when a control signal is not supplied, data and a status signal are transmitted by supplying the status signal to a data processor 10. Then, the data having a plurality of contents are transmitted by switching the contents of data to be transmitted corresponding to the control signal, and when the state of accepting no signal input from the data processor 10 is switched into signal input waiting state, a ready signal for repeating the change of a signal level is outputted as the status signal. In the state of accepting no signal input from the data processor 10, the busy signal of a fixed signal level is outputted as the status signal and when an error occurs at the time of receiving control instruction data, the output of signals is halted. |
