Assignment #4: "How To Measure (Almost) Anything"
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This week I also worked on a suggestion for an alternative serial connector.
Hello 3 board:
I left the resistor out for the time being.
Tested with the original step program, and it seems to work (obviously, the measurements themselves are not real since the circuit does not have the resistor).
The plan was to make a connectivity
tester - something that would beep or light up when we have a link with no
devices or resistance in between.
There seem to be 2 possible ways to do it:
The naive way: output Vcc to one measurement wire, and read the voltage coming out of the second wire. If the value is Vcc, it means there's a short between the 2 wires, and we have connectivity... The measurement will be to some threshold under Vcc, to allow for possible losses/degradation along our circuit. This is naive because we are counting on the user to set up the measurement in a logical way (e.g. on two points of the same line). This method can be fooled if, for example, we measure a Vcc equivalent value from another source.
Output some sort of predefined series of zeros and ones, and measure that we are reading the same value at the same time.
Eventually, most of the work this week had been done in learning groups. I worked mostly with the "voltage-meter" group, and learned about how the system works end-to-end. Reverse engineering is an important tool, and we set out to learn by understanding the original assembly and python codes, and modifying them to do what we want.
I've started to do the connectivity tester. After doing the voltage meter, this should be simpler.
Python: Indentation is extremely important in python. It doesn't matter if its 2, 3, 4 or 8 spaces or tabs, it just has to be consistent for the entire script.