Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [rfm69]

9 questions
4
votes
2 answers

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 value and then read it to make sure my write code…
Sam Hammamy
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2
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0 answers

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 the radio module to get stuck and I have to reset…
stenio
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2
votes
3 answers

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 read the version from the REG_VERSION register at…
Sam Hammamy
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1
vote
1 answer

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 connected to a RFM69HCW, which uses the SPI interface and…
Tøgern
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1
vote
2 answers

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 the wavelength (i.e. 20x20 mm board vs 700 mm or…
FarO
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0
votes
2 answers

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 and redo my board? I'd prefer to not have to spend…
1W0n_29
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0
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0 answers

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 other boards using the same module break out DI1…
richbai90
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0
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1 answer

strange RFM95 SPI behaviour with STM32L4

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 byte from an address, I have to send 1 byte, MSB set…
jbird
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-1
votes
2 answers

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 receiver is for the ground station. As far as we've…
Faruk UNAL
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