[NTLK] Implant 2017

Jake Bordens jake at allaboutjake.com
Sun Mar 26 17:24:32 EDT 2017

>>  I read in the SA1100 docs that you’re supposed to use 1v peak-to-peak signal when clocking the processor from an external clock generator. 
>>  I tried this and it didn’t seem to work, so I’m doing the same thing that the original implant did, and just use a 3.3v signal. (Not sure if this is a good or bad idea)
>   I think that this is fine. Great idea, great execution!

Yeah, according to those same docs, there are static protection clamping diodes on the clock input, so I think the diodes will protect even if the clock signal is a little hot… but they say it introduces noise/error.  I’m not particularly worried about it.  Eventually I want to do a burn in test and run it for a while and see how it behaves.

I also wrote a new routine to estimate the MHz of the processor.  Basically it compares the RTC to the processor ticks.  The original Implant had an app written in NSBasic to do this, but since it was NSBasic, it took a long time to synchronize the clock (the RTC only has 1-second resolution). With C code you can do this quicker by watching the RTC register directly.


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