Wireless data communication

摘要

A wireless data communication system involves two types of data packets. A first type requires a response from a receiving apparatus and a second type that does not require a response from the receiving apparatus. A transmitting apparatus (10) determines that a packet of the second type has been sent by checking whether its data has left a transmission buffer (15). A flag (15a) is provided to indicate whether a packet's data is in the buffer (15).