How to make sense of Struct data received from Arduino in RPi via NRF24?

[nrf24_is_hard]

Hi guys,

I know that for a simple transmission e.g. humidity and temperature, the Arduino can simply fit these into a float array and send it to the RPi.

The RPi can then execute the following code snippet to get the value:

DataBytes=8
receivedMessage=bytearray(DataBytes)
radio.read(receivedMessage,radio.getDynamicPayloadSize())
data = struct.unpack('ff',receivedMessage)
humidity=data[0]
temperature=data[1]

Arduino snippet:

struct values{
char name[15];
float temp;
float humi;
float light;
float soilMoist;
float soilTemp;
float gasSensor;
float pirSensor;
};
struct values DataToSend;
DataToSend.temp=dht.ReadTemperature();
//continue storing data in DataToSend
radio.write(&DataToSend,sizeof(DataToSend))

My question is now, how would I send this struct from the Arduino to the RPi with a similar method like the float array?

[OldSurferDude]

@nrf24_is_hard When I sent data between an Aduino and the RPi I discovered that I have to make the the receiving and the sending structs the same size AND the variables be on 4 byte boundaries. Change your char name[15] to char name[16]

Another challenge is that the number of bytes of type int are different. If I remember correctly, Arduino Uno is 2 bytes and RPi is 4 bytes.

To make matters worse, some compilers make the least significant byte the first byte of a word and others make it the last byte of a word. eg, sending the value 1 would be received as 16777216 (0x00000001 vs 0x01000000)

There are a lot more gotcha's ;)

OSD