DIY :- Wireless Chat Using RFM70
The embedded packet processing engines enable their full operation with a very simple MCU as a radio system. Auto re-transmission and auto acknowledge give reliable link without any MCU interference.
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For the communication between Microcontroller and RFM70 module you have to use SPI protocol many controller gives the Hardware SPI but in this project we are going to use Software SPI.
Data which is received by the Microcontroller is now transffered to the RFM70 and RFM70 transmit that data in RF.
This is all about the Transmitter and for the Receiver it will do the same procedure but in reverse order first RFM70 Module collects the Data from RF and then on the request from Microcontroller via SPI Command it gives the received data to Microcontroller and the same data now also available on the other Computer or Laptop.
Microcontroller Section
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Now as we are going to interface controller with MAX232 and RFM70 there are CE,CSN,SCK,MOSI,MISO and IRQ signals are used to communicate with RF Module and RXD,TXD to communicate with Serial Port of PC.
Now Before we start SPI Communication with RF Module you must have knowledge of SPI. for that again refer #-Link-Snipped-# for Some basic Information about SPI.
Note:- Remember as the RF module is working on 3.3Volt you must have to choose MCU which is working on 3.3 Volt. Here MCU_SUP is 3.3Volt
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