高级链路层协议的实现，vhdl，fpga,- 8 bit parallel backend interface - use external RX and TX clocks - Start and end of frame pattern generation - Start and end of frame pattern checking - Idle pattern generation and detection (all ones) - Idle pattern

这是一个优秀的Telcom公司开发的Q921商用协议栈，已在很多项目中使用并验证。实现了完整的Q921 LAPB和LAPD协议栈-This is an excellent Telcom developed Q921 commercial protocol stack has been used in many projects and verify. To achieve a complete Q921 LAPB and LAPD protocol stack

实现LAPD帧的校验、插值和去插值函数,既封包和解包处理-LAPD frame to achieve the calibration, interpolation and the interpolation function to

　该消息由网络侧向被叫用户发送的，用来标识该被叫用户已经被授予该连接通路。该消息也会由主叫用户向网络侧发送，用来确认对称的通路连接控制过程。 LAPD: 0 R (F) I-frame (NR=2e NS=5e) Q.931-BRI: ref=0x001a CONN ACK < 1: ( 9) 2751348 < 00 01 bc 5c 46 02 00 1a 0f -　该消息由网络侧向被叫用户发送的，用来标识该被叫用户已经被授予该连接通路。该消息也会由主叫用户向