md由于机器的复杂性所以没有mesen这种集大成的模拟器，而且mesen作者比较勤奋也是一个很重要的原因，md模拟器普遍更新较慢进度和mesen没法比。说一下目前比较好的几个吧
精度较高的目前来说是blastem，Genesis Plus GX和Exodus，但它们目前都不支持32x和pico，且只有Genesis Plus GX支持md-cd，好处是它们还在更新，支持是迟早的事，就是不知道这个迟早是什么时候。易用性都比较一般，Genesis Plus GX甚至都没有单独的模拟器程序，它只是提供一个模拟核心而已，要用的话你需要libretro，换句话说得用retroarch或者bizhawk，推荐用bizhawk
目前支持md-cd和32x（pico暂且放一边）的只有kega fusion，部分gens系和PicoDrive（MAME也支持但我相信没几个人去用MAME玩md吧）。前面两个无一例外都早已经停更了，fusion被很多md模拟器玩家吹上天，当年确实牛，fusion甚至是第一个支持当时已知所有md卡带的模拟器（太阳码头等后来才出的游戏是后话），但那都多少年前的黄历了，不仅精确度，兼容性都被后来居上，对新系统的支持也是个大问题。易用性方面实际也不如某些gens系，gens-rr无论从易用度还是功能方面都超过fusion一截，精度也不比fusion差。PicoDrive是开源模拟器还在更而且它支持pico（当然fusion也支持，gens系不支持），支持libretro，这意味着你可以用retroarch等玩md-cd和32x
单独提一下fbn（finalburn neo），这个街机模拟器和mame一样也能玩md游戏，比较好用，不过不支持cd和32x
我个人认为，仅从游玩的角度来说，gens-rr大概能解决99%的问题（虽然也停更快10年了），是比较实惠的方案，剩下1%可以交给Genesis Plus GX（bizhawk，retroarch），看你自己喜欢吧，如果非要找一个大一统的话，那只能是retroarch了
未来我比较看好blastem和Exodus，这两个定位就相当于fc的mesen，而且还在更新

md的模拟器在DOS时代就模拟的很好了

手机端我一直用md.emu，其他不太了解，pc端我看很多国外模拟器站推荐的基本就那两个。

所以说人菜还喜欢自己给东西下定义，时序模拟是你这个意思？就和之前说的封建社会一样，是你理解的那个意思吗？随便摘一段模拟器时序精确的定义，自己看
Most emulators are extremely inaccurate when it comes to timing. The reason for that is that there's often a huge performance tradeoff involved. In a real system, you might have half a dozen or more discrete devices all doing things at the same time. Each device might run at its own rate with its own performance characteristics. In a real system, those devices are not completely isolated, that wouldn't be a very useful system, those devices need to interact. When you're emulating that system, how do you ensure that every single device access occurs in the correct order though? The simple fact is, most emulators do not. Most emulators aim for a certain degree of timing accuracy, which is usually just enough to emulate some particular set of existing programs that run on that platform, and that's as accurate as they get. Timing related bugs often become the biggest roadblock to increasing emulation accuracy as an emulator advances, and increasingly become more and more difficult to solve. So, how do you solve timing problems with 100% accuracy? Well, the first, most obvious way, is to run every device in what's called "lock-step". This is simply to advance every device in the system one by one, advancing each device by a single "step", ensuring that no device gets ahead of another. This works with 100% reliability. It's also very, very, very slow. The biggest problem this approach has is that you reduce your emulator to a single-threaded model, because everything always has to wait for everything else, so you can't really do anything in parallel. Since we now live in the age of parallel computing, this effectively cripples the performance of your emulator now and into the future. That leads into the next topic.

所谓的时序模拟，简单的说，就是一个主机的所有硬件真实同序模拟运行，而不是有一个部件因为模拟不精确跑得过快造成了系统整体不同步，这就不是时序精确了，根本就不是你yy的那一套好吗