NEC follows a pattern for each firmware revision: 2.xy, where:

X = Type (Retail, OEM, Rebadge)
Y = Revision number

Till today know patterns:

X = 0 (OEM)
X = 1 (Retail)
X = 2 (HP/IO Data)
X = 7 (TDK)
X = B (Ricoh)
X = F (MadDog)
----------------------
Y = 6
Y = 7
Y = 8
----------------------

Combining the above info for example we have

* 2.x6 (2.06/2.16/2.76/2.F6)
* 2.x7 (2.07/2.77)
* 2.x8 (2.F8/2.78) etc...

While the 2.x6 builds supposed to be the same, there is high possibility that due to writing strategy and release data differences, some of them are newer and hopefully better.
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這樣子你懂了嗎...大概是破解版跟其它家OEM/ODM的韌體把你攪的亂七八糟了...
其實真正的 NEC 正版韌體最新為 2.17 (2004/10/5發布)...
2.18 大概下禮拜左右就會提出來了...片子的支援性應該會大增!!