终于在5410的DATASHEET中 INTERRUPT TIMING部分找到
The external interrupts (INT0−INT3, NMI) are synchronized to the core CPU by way of a two-flip-flop synchronizer that samples these inputs
with consecutive falling edges of CLKOUT. The input to the interrupt pins is required to represent a 1−0−0 sequence at the timing that is
corresponding to three CLKOUTs sampling sequence.
另外在TI网站上找到一个类似的问题及解答
http://www-k.ext.ti.com/srvs/cgi-bin/webcgi.exe?Company={5761bcd8-11f5-4e08-84e0-8167176a4ed9},kb=dsp,case=31784,new
Are the C55x DSP interrupt pins level- or edge-triggered?
Problem:
Are the C55x DSP interrupt pins level- or edge-triggered?
Solution:
It can be considered as edge triggered (falling edge) but with an additional low pulse width requirement. A sequence on the interrupt pin of a logic one followed by several 0s on consecutive cycles is required for an interrupt to be detected. See the External Interrupt Timings section of the data manual for details.
结论:C54与C55外部中断触发方式基本一样 ,类似边沿触发,CLOUT下降沿采样,但是对PIN的电平有要求。。
如5410需要1-0-0
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