A method of dividedly transmitting a message data, which message data is sent in a plurality of message packets, each message packet having a predetermined format, and each message packet having a predetermined data field amount, even if a data amount of message data exceeds an allowable amount of data, said method comprising the steps of:
- displaying input message data and an indicator for indicating a range of input message data exceeding the allowable amount;
- sequentially transmitting blocks of said message data, to each of which connection information indicating a connection relation between the blocks is attached, as a part of the message packet data field amount, when said input message data is in excess of said allowable amount;
- and
- sequentially displaying the blocks of said message data.