diff --git a/Images/programming.png b/Images/programming.png new file mode 100644 index 0000000..98c8a08 Binary files /dev/null and b/Images/programming.png differ diff --git a/README.md b/README.md index 1f36342..f626e61 100644 --- a/README.md +++ b/README.md @@ -19,7 +19,7 @@ Other than the assembled PCB, an antenna is required. For a basic quarter wave c * For 433 MHz, use a 165mm * For 220 MHz band, Use 324mm -If powered by a button cell battery, solder on a [MY-2032-12](https://www.lcsc.com/product-detail/Battery-Connectors_MYOUNG-MY-2032-12_C964833.html) battery connector. Other similar CR2032 holders work as well, but may require trimming the solder leads to fit the footprint. +If powered by a button cell battery, solder on a [MY-2032-12](https://www.lcsc.com/product-detail/Battery-Connectors_MYOUNG-MY-2032-12_C964833.html) battery connector. Other similar CR2032 holders work as well, but may require trimming the solder leads to fit the footprint. Melt a little solder on the negative battery terminal before soldering on the battery holder to ensure proper electrical contact. If powered by an external battery (e.g. 1s lipo), connect to the V+ and GND pins. Note that it doesn't have reverse polarity protection, so double check the polarity! @@ -29,16 +29,22 @@ The firmware can be modified and compiled with [STM32CubeIDE](https://www.st.com The main code is located in `Firmware\Core\Src\main.c` -Programming the firmware can be done with [STM32CubeProg](https://www.st.com/en/development-tools/stm32cubeprog.html) and a cheap UART to USB dongle (Search "ftdi adaptor" and get one of the red dongles 6 pins) +Programming the firmware can be done with [STM32CubeProg](https://www.st.com/en/development-tools/stm32cubeprog.html) and a cheap UART to USB dongle (If you don't have one, search "FTDI adaptor" and get one of the red dongles with 6 pins) * Disconnect power * Hold down the button -* Connect the FTDI adaptor to the beacon (make sure Rx goes to Tx and Tx goes to Rx). If unsoldered, hold them at an angle to ensure proper contact. +* Set UART adaptor to output 5V power with the jumper, though 3.3V should work as well. +* Connect the UART adaptor to the beacon (make sure Rx->Tx, Tx->Rx, GND->GND and VCC->V+). If unsoldered, hold them at an angle to ensure proper contact as shown below. * LED should be continuously ON, indicating it has entered bootloader mode. * In STM32CubeProg, select the UART option and port. Then connect to the MCU. * In the Erasing & Programming tab, pick the right firmware `Firmware\Debug\rocketbeacon.elf`, and program * Cycle power to execute the code. +![programming](Images/programming.png) + +## Reception and tuning +Tune your radio to the programmed frequency. Without calibration, the frequency has a tolerance of roughly +/- 5 KHz in the 70 cm band. + ## Configuration TODO: Make a little UART configuration interface to set frequency, callsign etc. \ No newline at end of file