正如这里的许多人已经说过 Xilinx 是 FPGA。FPGA 是“软逻辑”,因为您使用类似的开发过程来开发 ASIC,但您可以在硬件上测试您的设计,而无需制造厂这样做。权衡是速度,他们实现“元逻辑”而不是布局由传统“nand-nand”或“nor-nor”逻辑组成的设计,他们具有可编程查找表,可以编程以实现任意逻辑门。这在概念上与为处理器而不是本机代码运行解释器是相似的。
虽然您无法获得与使用 asic 相同的性能,但它允许小批量产品具有 asic 的大部分优势,而无需在 FAB 工厂进行生产运行的成本。此外,您可以将 FPGA 更多地视为软件设计,并为不同的操作模式加载不同的比特流。Xilinx 和 Altera 都有开发套件,可让您将设计存储在紧凑型闪存中,并在启动时选择不同的映像。
对于嵌入式设计,FPGA 为您提供了通常无法从现成的处理器中获得的东西,您的设计可以拥有您需要的确切硬件,您不必寻找 1000 个不同的微控制器来找到“完美匹配! " 最重要的是,我已经看到使用 16 位或 32 位处理器的旧系统迁移到 FPGA 并实现了比基于处理器的设计更好的性能、更低的成本和更低的功耗。包含“正确的”硬件有一些话要说。
Both VHDL and Verilog are high level langauges and while different from C and C++ they aren't significantly harder just different and require a different thought process. You don't get a lot of built in libraries to do everything for you, so you might wind up getting "Cores" off sites like "OpenCores.com" and connecting them together to implement your designs, with the additional logic you need. FPGA code is going to generally be parrallel, you have to specifically implement serial behaviours, and you have to take into considerations pipeline stages and delays. So while the languages themself aren't more difficult, some of the concepts maybe. But they are also more rewarding, kinda like building a house instead of writing about a house.