Turn-key PCB assembly services in prototype quantities or low-volume to mid-volume production runs

RF communication channel for microcontroller based devices

Wireless communication is always interesting. First of all it frees us from wires and increase distance between sender and receiver. You can get lot of advanced RF modules like Zigbee, bluetooth, GSM WiFi. But they are more expensive and not always necessary to have simple RF channel. Simple RF modules may do job well. They cost pennies and are pretty easy to work with. Usually they come in frequencies 315Mhz and 433Mhz. These modules dont have any modulators or encoders. They simply modulate and transmit what ever you give to DATA pin. So obviously some data encoding/packeting mechanism is needed. If microcontroller is used simple USART connection may work pretty well. But this is not very reliable way. If you want to free MCU from encoding tasks then there are special encoder/decoder chips (HT12E and HT12D) that takes parallel data from MCU and forms data packet to be transmitted. Receiver decodes this packet and produces same signal on output like they were sent using wires. Bhargav shares with details on how to set up transmitter and receiver with decoders and… Continue reading

Infrared and RF transceiver projects with PIC

This is really cool remote control project that uses two communication links – IR and RF. The whole project consist of three main parts as separate boards: 4/8 channel RF transmitter, 4/8 channel IR transmitter and 4/8 channel IR/RF receiver. Each of transmitters have 8 buttons. Transmitters can act as 8 channel transmitter for sending simple codes or four channel transmitter for sending ON and OFF command with button pairs. The receiver module has 8 relays. Receiver module can be equipped only with RF or IR module- base circuit is same. I wander why not to use both receivers and make it more universal… Source codes for PIC microcontrollers for all transceiver variations are available for download and can be compiled with MPLAB. Continue reading