集成电路的数据手册中经常出现assert和deassert二个单词,有很多人把assert译成"断言",但是我觉得译为"有效"更为符合实际.deassert译为"无效".
例如:某数据手册中写道The address line ADD is asserted at time t1 and is deasserteed at time t2.接下来给出的时序图中可以看出,ADD信号在t1时变成高电平,t2时变为低电平.我们可以译为:"地址线ADD在t1时有效,在t2时无效."
也有人说可以把assert译为"置位",deassert译为"清零",但是我认为这样不妥.因为对于低电平有效的信号,assert代表的是清零,而不是置位.例如PXA270的数据资料中有一段话:The external power-control subsystem de-asserts nBATT_FAULT to signal that the main
battery is connected and not discharged.这句话的大意是:nBATT_FAULT引脚是高电平时,表示主电池正常.显然,些处把de-assert译为清零是不对的,而应该译是"无效".
今天在看PXA270数据手册时发现了INTEL对assert和deassert的解释(第40页).解释如下:
assert: Drive a signal to its active voltage level, either high or low.
deassert: Drive a signal to its inactive voltage level, either high or low.
总结：
assert: 使有效
deassert: 使无效