Documentation for the GY-271 electronic compass breakout board, a small three-axis magnetometer module, supplied as a 626 KB PDF. The document is useful for identifying the module pinout, supply voltage, I2C interface lines and the sensor chip it carries. When a compass reading is wrong or absent, the technician can check power on the module, pull-ups on SDA and SCL, and the bus address against this reference. GY-271 boards have been produced with different magnetometer chips, so read the marking on the sensor IC and confirm it matches the datasheet.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @datasheet. Enginerys does not host this file.
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