https://devzone.nordicsemi.com/f/nordic-q-a/90435/building-y-project-using-make-fileI had this error while building my project and compiling my lsm9ds1.c driver, the nrf_drv_twi.h file couldn&#39;t be compiled! integration/nrfx/legacy/nrf_drv_twi.h:120:37: error: &#39;NRF_DRV_TWI_INSTANCE_1&#39; undeclared here (not in a function); did you meanen-USTelligent Community 13Thu, 28 Jul 2022 11:53:44 GMThttps://devzone.nordicsemi.com/thread/379111?ContentTypeID=1Thu, 28 Jul 2022 11:53:44 GMT137ad170-7792-4731-bb38-c0d22fbe4515:ea908086-eb0b-4f57-addd-b7ed8b29de8dJ&#248;rgen Holmefjord<p>Hi,</p> <p>What did you pass as the argument to&nbsp;<span>NRF_DRV_TWI_INSTANCE()? If you are passing a define, make sure you remember to define it in your code.</span></p> <p><span>Also make sure you set &quot;TWI1_ENABLED&quot; to 1 in your sdk_config.h file.</span></p> <p><span>Best regards,<br />Jørgen</span></p><div style="clear:both;"></div>