diff --git a/README.md b/README.md index b3bb648..b4dd016 100644 --- a/README.md +++ b/README.md @@ -1,4 +1,44 @@ # Exploded_Mini17 -STM32+CC1200 evaluation board +This is an exploded version of the [Mini17](https://github.com/M17-Project/Mini17) UHF handheld tranceiver, a [TR-9](https://github.com/M17-Project/TR-9) successor. Its purpose is to allow for experimentation with the [CC1200](https://www.ti.com/product/CC1200) chip and its M17 use. In other words, it's an STM32+CC1200 evaluation board. + +## Flashing +To enter the DFU mode, keep BTN2 pressed while powering the board up. + +## Hardware +The Exploded Mini17 has all the peripherals a walkie-talkie development board should have: +* GD32/STM32F405RGT6 micro with most of the unused pins available at the 2.54mm pin headers, +* RF front end built around CC1200 chip, +* 90° SMA connector, +* set of 3 buttons, +* microphone and a 1W speaker, along with amplifiers, +* USB-C connector for programming and power supply. + +### Connector list + +| Designator | Function | Remarks | +|--------------|-------------|---------| +|`CN1`|External power supply|6..15V| +|`CN2`|External Button 1|Low-active| +|`CN3`|External Button 2|Low-active| +|`CN4`|External interrupt|Max. 3.3V| +|`CN5`|External Button 3|Low-active| +|`CN6`|External speaker output|≥8ohms, set `U6`/`U7` jumpers accordingly| +|`CN7`|External microphone input|set `U10` jumper accordingly, bias provided by `U9`| +|`H1`|GPIO port, 3 I/O lines|Max. 3.3V| +|`H2`|SWD|| +|`H3`|GPIO port, 3 I/O lines|Max. 3.3V| +|`H4`|GPIO port, 11 I/O lines|Max. 3.3V| +|`H5/ANALOG`|Analog I/O port|Max. 3.3V| +|`H6`|GPIO port, 6 I/O lines|Max. 3.3V| + +### Test point list +| Designator | Function | Remarks | +|--------------|-------------|---------| +|`TP1`|Speaker output signal, negative|| +|`TP2`|Speaker output signal, positive|| +|`TP3`|Audio DAC output signal|| +|`TP4`|Speaker amplifier input signal|| +|`TP5`|Microphone signal|DC-biased| +|`TP6`|Amplified microphone signal|DC-biased|