摘要 |
PURPOSE:To form a miniature good-operation key unit by using nonlock keys, by sending key information, stored in a memory circuit, as effective information when a key telephone set has its handset off the hook within a certain time. CONSTITUTION:Information on the hook switch and keys in key hook-switch unit 1 is stored in key information input circuit 2 temporarily. When the handset is placed in the off-hook state, off-hook information is outputted to hook information output line 3 and depressing keys in unit 1 sends key information to key information output line 4 corresponding to keys. Then, key information on nonlock keys depressed corresponding to a key telephone set is stored in memory circuit 5. A certain time after the nonlock keys are depressed is measured by time measuring circuit 6. When the key telephone set has the handset off the hook within the certain time, the key information stored in circuit 5 is sent out 7 as effective information. Thus, the miniature good-operation key unit can be formed by using the nonlock keys. |