基于FPGA的数字频率计设计+电路图
毕业论文关键词：Verilog HDL FPGA 频率计
The Digital Frequency Meter Based on FPGA
Abstract Frequency measure is widely used in the field of electronic measurement. Toimprove accuracy, the sensor module is commonly used to convert temperature, flow,PH value, the percentage of various gases and other parameters into a frequencysignal to be measured by a frequency meter. By this means, we can improve theaccuracy.Using traditional frequency meter to measure the signal, the measurementaccuracy will change with the change of the signals. In order to overcome theshortcomings this system designed a digital frequency meter based on FPGA by usingVerilog-HDL. This design uses equal precision frequency measurement method, sothat the measured signal and the standard signal can be measured simultaneously inthe same gate time. The electronic counting function is converted to test multi-cycle.The system can measure a sine wave, square wave and the triangular wave three typesof signals. Test results show that measuring frequency range is 1Hz to 10MHz; Theerror is controlled in about 1% when signal is the low-frequency signal (1Hz ~1000Hz); And the measurement error is about 0.0052 ‰ when measured signal ishigh-frequency signals ( 1MHz ~ 10MHz).
KeyWords：Verilog HDL FPGA Frequency meter
目录
摘要..I
AbstractII
图清单..V
表清单..V
1绪论..1
1.1研究背景和意义.1
1.2发展现状与趋势.1
1.3FPGA概述及发展现状...2
2系统方案分析及比较选择3
2.1方案构想.3
2.2方案比较及选择.4
3工作原理及系统框图5
3.1直接测频法原理及误差分析5
3.2直接测周法原理及误差分析6
3.3等精度测量原理及误差分析7
4硬件设计.9
4.1FPGA最小系统9
4.2整形电路...10
4.3液晶显示模块...11
5软件设计...12
5.1VerilogHDL介绍...12
5.2预置闸门信号产生模块..13
5.332位除法器模块..13
5.432位乘法器模块..14
5.5计算频率值模块...15
6系统调试与分析...17
7总结18
参考文献19
1 绪论1.1 研究背景和意义在数字电路中，频率计属于时序电路的范畴，它是由各种触发器构成的，而且这些触发器均具有一定的记忆功能。无论是在计算机还是其他的各种数字仪表中，数字频率计都已经得到了普遍的应用。现如今，随着电子技术、数字技术及计算机科学等诸多不同技术领域的不断发展，电子计数器广泛地使用大规模集成电路，做到与微处理器有机的融合，数字频率计也因此时时得到改进与完善[1]。 传统的频率计通常有着不可忽略的测量误差，本课题设计了一种基于 FPGA 的等精度测量频率计，充分应用 FPGA的高速数据采集技术，设计原理简约、测量精度高、电路相对稳定，有效地减少了生产周期。