我对 FPGA 领域还比较陌生，希望获得使用 FPGA 和 VHDL 的经验。我不太确定使用标准 MCU 的好处是什么，但正在寻找经验，因为许多公司都在寻找它。
什么是一个很好的平台，可以开始并以不多的钱获得经验。我一直在寻找，我能找到的只有 200 - 300 美元的主板，如果不是 1000 美元的话。人们应该在 FPGA 开发板中寻找什么，我听说过高速外设接口，我想我真正困惑的是，具有大约 50/100 GPIO 的 MCU 开发板可以达到大约 100 个，而在相同的功能上FPGA板要贵得多！我知道您可以重新编程 FPGA，但 MCU 也可以。我是否应该摆弄 FPGA，市场会继续使用它们，还是我们只转向 MCU？
I'm relatively new to the FPGA sceen and was looking to get experience with them and VHDL. I'm not quite sure what the benefit would be over using a standard MCU but looking for experience since many companies are looking for it.
What would be a good platform to start out on and get experience for not to much money. Ive been looking and all I can find are 200 - 300 dollar boards if not 1000's. What should one look for in an FPGA development board, I hear high speed peripheral interfaces, and what I guess I'm really confused about is that an MCU dev board with around 50/100 GPIO can go for around 100 while that same functionality on an FPGA board is much more expensive! I know you can reprogram an FPGA, but so can an MCU. Should I even fiddle with FPGA's will the market keep using them or are we moving towards MCU's only?
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嗯...我很快就找到了三个低于 100 美元的评估板：
79 美元：http://www.terasic.com.tw/cgi-bin/page/archive.pl?Language=English&No=593
79 美元：http://www.arrownac.com/solutions/bemicro-sdk/
89 美元：http://www.xilinx.com/products/boards-and-kits/AES-S6MB-LX9.htm
至于在评估板中寻找什么，这完全取决于你想做什么。如果您要完成特定的设计任务，您需要一块支持与最终电路一样多的相同功能和 I/O 的电路板。您可以获得具有各种内存选项（SRAM、DDR2、DDR3、闪存等）、以太网、PCI/PCIe 总线、高速光纤收发器等的主板。如果您只是想开始，几乎任何主板都适合您。事实上，今天出售的任何产品都应该有足够的空间，即使是不平凡的示例设计（即：使用软核 CPU 构建您自己的微控制器并设计/选择您自己的外设组合）。
即使您的主板只有几个开关和 LED，您也可以开始设计硬件“Hello World”（又名闪烁的 LED:)、简单的状态机和许多其他应用。你从哪里开始以及你尝试做什么应该取决于你的总体目标。如果您只是想获得 FPGA 的一般经验，我建议：
对于继续使用 FPGA 的市场，他们肯定会留在这里，但是并不意味着它们适合所有应用。 MCU 本身适用于许多应用，但无法处理所有情况。例如，您可以轻松地使用大多数微控制器“bit-bang”I2C 甚至串行 UART，但是如果没有一些定制硬件，您将很难与以太网端口、VGA 显示器或 PCI/PCIe 总线进行通信。由您决定如何混合可用技术（MCU、FPGA、内部设计的自定义逻辑、许可的 IP 核、现成的标准硬件芯片等）来创建功能产品或设备，并且通常没有任何单一的“正确”答案。
Hmm...I was able to find three evaluation boards under $100 pretty quickly:
$79: http://www.terasic.com.tw/cgi-bin/page/archive.pl?Language=English&No=593
$79: http://www.arrownac.com/solutions/bemicro-sdk/
$89: http://www.xilinx.com/products/boards-and-kits/AES-S6MB-LX9.htm
As to what to look for in an evaluation board, that depends entirely on what you want to do. If you have a specific design task to accomplish, you want a board that supports as many of the same functions and I/O as your final circuit. You can get boards with various memory options (SRAM, DDR2, DDR3, Flash, etc), Ethernet, PCI/PCIe bus, high-speed optical transceivers, and more. If you just want to get started, just about any board will work for you. Virtually anything sold today should have enough space for even non-trivial example designs (ie: build your own microcontroller with a soft-core CPU and design/select-your-own peripheral mix).
Even if your board only has a few switches and LEDs you can get started designing a hardware "Hello World" (a.k.a. the blinking LED :), simple state machines, and many other applications. Where you start and what you try to do should depend on your overall goals. If you're just looking to gain general experience with FPGAs, I suggest:
As for the market continuing to use FPGAs, they are definitely here to stay, but that does not mean they are suitable for every application. An MCU by itself is fine for many applications, but cannot handle everything. For example, you can easily "bit-bang" an I2C or even serial UART with most micro-controllers, but you would be hard pressed to talk to an Ethernet port, a VGA display, or a PCI/PCIe bus without some custom hardware. It's up to you to decide how to mix the available technology (MCUs, FPGAs, custom logic designed in-house, licensed IP cores, off-the-shelf standard hardware chips, etc) to create a functional product or device, and there typically isn't any single 'right' answer.
如果您需要部分或全部以下功能，FPGA 会胜过微控制器：
如果没有，那么使用微型或 DSP 可能会更好。
FPGAs win over microcontrollers if you need some or all of:
If not, then you are likely better off with a micro or DSP.
OpenCores 网站是一个极好的资源，尤其是 编程工具部分。网站上的文章链接是开始调查 FPGA 板的好地方。
FPGA 相对于微处理器的最大优势在于架构。微处理器具有一组固定的功能单元，可以很好地解决大多数问题。我见过微处理器的计算效率为 6% 到 15%。在 FPGA 中，您可以专门针对您的问题创建功能单元，而不是其他任何东西，因此您可以达到 90-100% 的计算效率。
至于成本差异，请考虑销量。微处理器销量高，而 FPGA 销量相对较低。
The OpenCores web site is an excellent resource, especially the Programming Tools section. The articles link on the site is a good place to start to survey FPGA boards.
The biggest advantage of an FPGA over a microprocessor is architecture. The microprocessor has a fixed set of functional units that solve most problems reasonably well. I've seen computational efficiency figures for microprocessors form 6% to 15%. In an FPGA you are creating functional units specifically for your problem and nothing else, so you can reach 90-100% computational efficiency.
As for the difference in cost, think of volume sales. High volume of microprocessor sales vs. relatively lower FPGA sales.