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You never reset your b pointer. The first time through it works its way through the memory reserved for buf. The second time through your loop it's already at the end of that memory and you then start incrementing (and filling) past that overwriting other variables - the first of which sounds like it might be n - so *b++=data is writing data (245) to n. You ...


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The SmartInventor library is to be used with the Rokit Smart board. That board is based around the ATMega32. The Arduino Mega is not a Rokit Smart board, so the library will not work, since the Arduino Mega us based around the ATMega2560. The two chips are different, and have different sets of internal peripherals. So the registers have different names ...


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While it is true that your loop is incorrect, the coding error is unlikely to cause the behaviour that you have described. Please ensure that a current limiting resistor is placed in series with each LED. Since you have 14 LEDs, you will need 14 current limiting resistors. 470 Ohm resistors (or similar) should be adequate for this purpose. As per the other ...


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The BMP180 uses the I2C bus and you cannot simply turn off the device, since that can block the I2C bus. Also it has only one, not changeable address. Thus you would need one I2C bus for every BMP180. So know you have 2 ways to go: You could use a Software I2C library and define one I2C port for each BMP. That would use 12 digital pins and you need to find ...


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The library, that you are using, doesn't seem to support exporting or importing fingerprints. Though if you look into the user manual of the fingerprint sensor at the Adafruit site, there are two commands mentioned, that seem to do what you need: 6.2.2 Upload image: UpImage Description: to upload the image in Img_Buffer to upper computer. ...


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There is no real multitask on Arduinos. The Arduino can only do one thing at a time. But, you can do things sequentially, one after another, so fast, that a human will think, that it happens simultaneously. This involves a non-blocking coding style, which needs no interrupts Every delay in your code (at least the long onces) need to be removed. if you want ...


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