| 摘要 |
PURPOSE:To make it possible to receive information without error in PCM transmission by monitoring frame synchronization and multi-frame synchronization independently by a multi-stage counter constitution and synchronizing them with each other. CONSTITUTION:Counters CT-A to CT-G are provided, and CT-A, CT-B, CT-C, CT-D and CT-E count the number of bits in a unit, the number of units, the number of frames, error pulses of FF3 and normal pulses respectively, and fame step- out signal D and frame synchronization establishing signal E are outputted to reset CT-D. Meanwhile, CT-F counts error pulses of FF6 and CT-G counts normal pulses. Then, multi-frame step-out signal F and multi-frame synchronization establishing signal G are outputted to reset CT-F. Thus, frame synchronization and multi-frame synchronization are monitored independently and are synchronized with each other. |
