PURPOSE: To attain data transmission even when a data terminal equipment has no function of sending a specific key by allowing a master set to store a dial operation mode of a slave set and allowing the master set to connect the slave set to a trunk line in response to the off-hook of the slave set or the data terminal equipment when the dialing mode is the forced mode.
CONSTITUTION: A dialing mode of a slave set 24 is stored in advance in a master set 22 and the master set 22 connects a slave set 24 to a trunk line in response to the dialing mode stored in the master set 22 as to the slave set 24 when the slave set 24 makes dialing. In the case of the normal mode, only when a prescribed signal input such as input of '0' exists, the master set 22 connects the slave set 24 to the trunk line. Thus, even when a data terminal equipment 20 connecting to the slave set 24 is a data terminal equipment unable to make '0' dialing, the data terminal equipment 20 is connected to the trunk line by storing the dialing mode of the slave set as the forced mode to the master set 22.
KUMAGAI HIROSHI
MIZUNO MASASHI
WAKABAYASHI HAJIME
HORIGOME SEIICHI
NIPPON TELEGRAPH & TELEPHONE