Hi all,
Today I had a chance to use a friend's scope to test something. I programmed 20X2 with the simple program below and then tested the result using the scope:
And here is the result from the scope (it is a 50MHz digital scope - so I guess it can provide enough bandwidth for my today's test):
The reason for doing this, is that I want to make a very simple square wave generator using 20x2. The idea is just making a pin output high and low in selectable time intervals. I know that this will produce naive waveforms but for my current need it would be enough.
So as you see I put in my program to wait 1ms between each high and low state. but the result I get on scope is around 1.4ms so I was wondering if this is a expected number ot not.
Also about the low state, as you can see it is -40mV so I was again wondering if this should be 0 or not? I tried with a bypass capacitor between +/- pins of the chip and this went lower to -120mV again is this expected?
OR my testing idea is completly rubbish and I am doing it wrong? Would be nice to hear some comments from pro users!
Today I had a chance to use a friend's scope to test something. I programmed 20X2 with the simple program below and then tested the result using the scope:
Code:
main:
high 1
pause 1
low 1
pause 1
goto main
The reason for doing this, is that I want to make a very simple square wave generator using 20x2. The idea is just making a pin output high and low in selectable time intervals. I know that this will produce naive waveforms but for my current need it would be enough.
So as you see I put in my program to wait 1ms between each high and low state. but the result I get on scope is around 1.4ms so I was wondering if this is a expected number ot not.
Also about the low state, as you can see it is -40mV so I was again wondering if this should be 0 or not? I tried with a bypass capacitor between +/- pins of the chip and this went lower to -120mV again is this expected?
OR my testing idea is completly rubbish and I am doing it wrong? Would be nice to hear some comments from pro users!
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