Questions tagged [rfm69]
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17 questions
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DIY Fireworks Firing Controller - Issues Upgrading Design from RFM69 LoRa RFM95 Radio
I have an existing design for a wireless fireworks firing system (remote and field module) that use RFM69HCW packet radio(s) @ 915MHz to transmit wireless commands to each other. I recently upgraded ...
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SD card and RFM69 radio module on same SPI bus not working?
I am trying to operate a MicroSD card and an RFM69 radio module on the same SPI bus with an AVR 8-bit MCU without success. While the radio module (as usual) works just fine, SD card initialization ...
- 801
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Temperature susceptibility, frequency deviation and receiver bandwidth
For fun and to learn, I am writing a simple driver for RFM69HCW radio modules. So far I'm impressed of the high transmission reliability and the long range, but there is one thing I am unsure about.
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- 801
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Just -65 dBm, are simple wire antennas really that bad?
Short answer: No, they are not. See update below.
I am writing a simple driver with avr-libc for RFM69HCW radio modules. Transmitting and receiving single packages works fine so far.
I don't know much ...
- 801
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A simple way to verify that radio transmitter is working?
For fun and to learn, I am trying to transmit some data from one RFM69HCW ~900 MHz to another with an Atmega328p and "plain" avr-libc.
Initialization is okay I think; reading and writing ...
- 801
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331
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How to design Antenna for RFM69HW 433MHz on PCB?
I am currently working on a PCB with an RF module (RFM69), where I aim to establish an integrated antenna. The primary functionality of the PCB is to control a DC motor by processing commands received ...
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How do the sx1276 radio AFC, AGC, RSSI, FEI work in FSK mode (RX)?
The sx1276 radio (https://www.semtech.fr/products/wireless-rf/lora-connect/sx1276) is commonly used in LoRA mode but it also has an FSK mode, this Q is about the FSK mode used in packet mode. This ...
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433MHz Antenna PCB Trace Design
I have designed a custom PCB which among other things has an RFM69HCW (ignore the text on the PCB, it is wrong) capable of outputting +20dBm. The antenna connection is done using a PCB trace (42[mils] ...
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213
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Forgot to decouple RFM69HCW
I was in the middle of soldering a PCB I designed when I realized I forgot to decouple the RFM69HCW module with 0.1uF. Does anyone have any insight to how damaging this is, and if I need to redesign ...
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RFM69HCW Digital IO connection setup
I'm working to setup an RFM69HCW transceiver with an ARM microcontroller. I've read over the datasheet for the RFM69HCW and I see that DIO0 is the interrupt signal, so I've broken that one out, but ...
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RFM69 hat for RPI get stuck because of noise caused by missing ground
I built a RFM69 hat for a Raspberry Pi 3 B+. It works perfectly as long as I do not use the GPIO to switch on the relay that drives a solenoid valve. Unfortunatelly a lot of times the switching cause ...
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659
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Using FTDI with AtMega328P@3v3,8MHz and RFM69
I am running an AtMega328P-PU at 3v3, 8MHz with external crystal successfully. I am able to burn the bootloader using ISP and flash the chip using FTDI and the clock seems right.
The mega is ...
- 15
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RFM95/96 Multi Transmitter and One Receiver
We're working on a model rocket project. And we need two transmitters and one receiver. One of the transmitters is for the rocket body and the other is for the scientific payload in the rocket; the ...
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strange RFM95 SPI behaviour with STM32L4 [closed]
I am using CubeMX and HAL to program an STM32L4. I am trying to communicate with RFM96 module using SPI, but I am getting nonsensical results.
According to the RFM96 datasheet, in order to read a ...
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STM32 SPI not working as I expect it should based on online reading
I am using an STM32F103C8 to connect to a Hope RF95W transceiver IC for the purpose of learning.
I am only trying to read the chip version register, then write a config register that has a 0x00 reset ...
- 271
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Unable to get SPI working on STM32 Cortex-M3 (Blue Pill)
I am trying to connect to an RFM95W module using the Cortex-M3 Blue Pill from ST.
I am an embedded novice but know my way around linux, so I used the below code on an Rpi3 to connect to the chip and ...
- 271
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Half-wave coiled antenna or quarter wave straight?
The transmitters for hobby projects working on 433/868/915 MHz (RFM69) require an antenna connected to the board. The board is battery powered, without metallic chassis and overall much smaller than ...
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