https://devzone.nordicsemi.com/f/nordic-q-a/69806/nrf51-dongleAs per the document, this dongle has 5 GPIO pins for use. Can they be configured as I2C,SPI, RS232?en-USTelligent Community 13Mon, 28 Dec 2020 12:55:24 GMThttps://devzone.nordicsemi.com/thread/286693?ContentTypeID=1Mon, 28 Dec 2020 12:55:24 GMT137ad170-7792-4731-bb38-c0d22fbe4515:1b076c6c-c142-4a01-ba0a-212f63511c34Vidar Berg<p>The GPIOs can be used for I2C, SPI, and UART. RS-232 will require external components to convert the signal levels.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/286536?ContentTypeID=1Thu, 24 Dec 2020 05:16:54 GMT137ad170-7792-4731-bb38-c0d22fbe4515:c7f9c9c8-b3c6-4bc7-bc97-291a998f415avkadal<p>Just logic level. I think +/- 12 V RS 232 is no longer used</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/286385?ContentTypeID=1Tue, 22 Dec 2020 17:59:33 GMT137ad170-7792-4731-bb38-c0d22fbe4515:43871f16-2b21-49ca-ba05-a132f26808e1awneil<p>What does the nRF51 <strong>datasheet</strong> tell you?</p> [quote userid="93926" url="~/f/nordic-q-a/69806/nrf51-dongle"]RS232[/quote] <p>Do you really mean that - ie, +/-12V levels, etc - or do you just want logic-level UART comms?</p><div style="clear:both;"></div>