怎么知道给定引脚是什么类型的信号？

我已经阅读了一些关于使用Spartan3的5v设备的信息，我仍然对它持有信心。
如果我理解正确的话，你可以用一个串联电阻来限制电流，钳位二极管可以工作，允许5v输入而不会烧断它。
我看到提到VCCTTL33输入或类似的东西。
我想，33的电压为3.3伏。
还有2.5,2.0和其他。
你怎么知道给定引脚是什么类型的信号？
换句话说，鉴于VCCOTTL33（或其所称的任何东西）的计算显示为300欧姆串联电阻，您如何判断哪个I / O引脚可以使用300欧姆电阻设置？
我期待制作一个小板，将Playstation2控制器连接到我的S3BOARD。
由于我有大约1000个1k电阻器，所以我只想使用它们。
这会减慢信号的速度，但它应该可以工作。
我很担心，我不想炸毁我的董事会！
谢谢，
凯文



以下为原文

I have read a bunch of info on using 5v devices with Spartan3's and I am still leary about it. If I understand it correctly, you put in a series resistor to limit the current and the clamping diodes will work to allow 5v inputs without blowing it up. I saw mentions of VCCTTL33 inputs or something similar. The 33 makes 3.3 volts, I would think. There are also 2.5, 2.0 and others. How do you know what kind of a signal a given pin is? In other words, given the calculation for VCCOTTL33 (or whatever it was called) is showed as a 300 ohms series resistor, how can you tell which I/O pins will work with that 300 ohm resistor setup?

I am looking to make a small board that will interface a Playstation2 controller up to my S3BOARD. Since I have about 1000 1k resistors, I was thnking of just using them. This would slow down the signals, but, it should work. I worry alot and I don't want to blow up my board!

Thanks,
Kevin