From 47372b9179dc3125039a8ce4a6331389d8921d43 Mon Sep 17 00:00:00 2001 From: Mikael Nousiainen Date: Thu, 11 Nov 2021 18:39:31 +0200 Subject: [PATCH] Update README for GPS NMEA output and improve RS41 connector pinout description --- README.md | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/README.md b/README.md index 0e008cd..1b5a4ce 100644 --- a/README.md +++ b/README.md @@ -65,6 +65,8 @@ The main features the RS41ng firmware are: * Support for transmitting multiple modes consecutively with custom, rotating comment messages (see `config.c`) * Support for GPS-based scheduling is available for transmission modes that require specific timing for transmissions * Support for custom sensors via the external I²C bus +* GPS NMEA data output via the external serial port pin 4 (see below). This disables use of I²C devices as the serial port pins are shared with the I²C bus pins. + * This allows using the RS41 sonde GPS data in external tracker hardware, such as Raspberry Pi or other microcontrollers. * Enhanced support for the internal Si4032 radio transmitter via PWM-based tone generation (and ultimately DMA-based symbol timing, if possible) * Extensibility to allow easy addition of new transmission modes and new sensors @@ -172,14 +174,18 @@ ______________________| |______________________ * 1 - SWDIO (PA13) * 2 - RST * 3 - MCU switched 3.3V out to external device / Vcc (Boost out) 5.0V - -- This pin powers the device via 3.3V from an ST-LINK programmer dongle -* 4 - I2C2_SCL (PB10) / UART3 TX -- This is the external I²C port clock pin for Si5351 and sensors + * This pin powers the device via 3.3V voltage from an ST-LINK programmer dongle + * This pin can be used to supply power to external devices, e.g. Si5351, BMP280 or other sensors +* 4 - I2C2_SCL (PB10) / UART3 TX + * This is the external I²C port clock pin for Si5351 and sensors + * This pin can alternatively be used to output GPS NMEA data to external tracker hardware (e.g. Raspberry Pi or other microcontrollers) * 5 - GND * 6 - GND * 7 - SWCLK (PA14) * 8 - +U_Battery / VBAT 3.3V * 9 - +VDD_MCU / PB1 * (10k + cap + 10k) -* 10 - I2C2_SDA (PB11) / UART3 RX -- This is the external I²C port data pin for Si5351 and sensors +* 10 - I2C2_SDA (PB11) / UART3 RX + * This is the external I²C port data pin for Si5351 and sensors ### Steps to flash the firmware