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Weighing Scale

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Weighing Scale The system consists mainly of a 24-bit ADC for load cell sensing, a DSP for signal processing and a 8-bit microcontroller for interface. ADS1255 implementation A 24-bit converter was selected since the aim of the board is to serve as an interface to any of the load cells used across the different weighing points, without the need of an amplification stage. Thus making the calibration easier, in comparison with the current weighing system that requires manual adjustment of the amplifier gain. The menu interface is user-friendly. Calibration is achieved just by pressing a few buttons. First, zero offset correction is corrected by selecting "Calibration -> Zero". Then a full scale load is placed on the weighing platform, the option "Calibration -> Pattern" is selected, the user inputs the weight expressed in grams and then confirms. The system calculates the necessary parameters after which the system is ready to be used. Ma...

Digital Thermo-Hygrograph

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(UNDER CONSTRUCTION) This post, like others, is intended to be a more detailed description of my work and to share experience and advice with colleagues. If interested in the code, ask for git. The project was oriented to upgrade the sensor being used for experiments by members of the phytotherapy department of the National University of Central Buenos Aires. The specifications were a digital sensor capable of monitor the relative humidity and temperature of the greenhouse, where the experiments take place, saving the data of one week up to a month, powered by a 9v battery. The data should be downloaded with a computer in .csv format. The project was broken into several parts: Study of the alternatives. Budget elaboration. Realisation. Testing and validation. Starting with the study of the alternatives found into the market, the use of the si7021 A20 was the most convenient in terms of reliability, cost and instrumentation. The si7021 A20 is a relative humidit...