基于状态图的光电编码器4倍频vhdl程序，输入相位差90度的两相，输出倍频和方向信号-Based on the state of the optical encoder Figure 4 multiplier vhdl procedure, enter a 90-degree phase difference of two-phase, frequency and direction of the output signal

vhdl,Digital phase modulation is also known as phase shift keying, 2DPSK is binary differential phase shift keying, is a kind of digital phase modulation. Digital phase modulation using carrier phase change to transmit digital signal, usually can be

VHDL代码，源用与两路DDS之间的相位差，现可用于产生相位差可编程的1m时钟，精度可精确到0.01分。输出两路时钟，带起始控制位-VHDL code, source with the phase difference between the two DDS, can now be used to produce 1m phase programmable clock accuracy can be accurate to 0.01 points. Output two clocks with

采用FPGA（现场可编程门序列）编写VHDL语言设计多路同步脉冲发生器，对信号进行分频处理，实现四路信号相位相差T/16和T/8的延迟相位输出，实现的四路脉冲与传统的脉冲同步器不同，它具有高集成度，高通用性，容易调整和高可靠性等特点。(Using FPGA (field programmable gate sequence) to write VHDL language to design multi-channel synchronous pulse generator, to divide