Manchester Library Won't Compile for Attiny85

Question

I am creating a wireless sensor using an Attiny85. I want to send the data to an arduino uno, so I purchased the 315mhz rf link kit from spark fun. Since the Attiny85 does not have a TX I decided to use the Manchester library however it won't compile on the Attiny85.

I followed the steps from this blog : http://mchr3k-arduino.blogspot.mx/2012/01/wireless-sensor-node-part-2.html?showComment=1338749638806#c853067277980266192

Here is the code I am using:

    #include <WProgram.h> //otherwise it says it can't find Arduino.h
    #include <Manchester.h> //include the library to comunicate
    #define TxPin 2 //the pin that is used to send data

 int sensorPin = 4;
 int ledPin = 3;
 int count = 50;

 void setup(){
  pinMode (ledPin, OUTPUT);
  man.workAround1MhzTinyCore(); //add this in order for transmitter to work with 1Mhz Attiny85/84
  man.setupTransmit(TxPin, MAN_1200); //set transimt pin
}

void loop(){
  if (count == 50){
   digitalWrite (ledPin, HIGH);
   count = 0;
   }
   int data = analogRead(sensorPin);
   man.transmit(data); //transmits and reads the data
   delay (100);
   count ++;
 }

Here is the error message:

/Users/joelsimonoff/Documents/Arduino/libraries/MANCHESTER/Manchester.cpp: In function 'void MANRX_SetupReceive(uint8_t)':
/Users/joelsimonoff/Documents/Arduino/libraries/MANCHESTER/Manchester.cpp:366: error: 'TCCR2A' was not declared in this scope
/Users/joelsimonoff/Documents/Arduino/libraries/MANCHESTER/Manchester.cpp:366: error: 'WGM21' was not declared in this scope
/Users/joelsimonoff/Documents/Arduino/libraries/MANCHESTER/Manchester.cpp:368: error: 'TCCR2B' was not declared in this scope
/Users/joelsimonoff/Documents/Arduino/libraries/MANCHESTER/Manchester.cpp:368: error: 'CS21' was not declared in this scope
/Users/joelsimonoff/Documents/Arduino/libraries/MANCHESTER/Manchester.cpp:369: error: 'OCR2A' was not declared in this scope
/Users/joelsimonoff/Documents/Arduino/libraries/MANCHESTER/Manchester.cpp:379: error: 'TIMSK2' was not declared in this scope
/Users/joelsimonoff/Documents/Arduino/libraries/MANCHESTER/Manchester.cpp:379: error: 'OCIE2A' was not declared in this scope
/Users/joelsimonoff/Documents/Arduino/libraries/MANCHESTER/Manchester.cpp:380: error: 'TCNT2' was not declared in this scope

Answer 1

attiny is missing an option required to allow the Manchester library to function properly on ATtinyX5 devices, specifically definition of __AVR_ATtinyX5__ when a device is selected. In fact, it's missing quite a few things.

The package I use for ATtinyX5 support is arduino-tiny. I have verified that it defines that symbol properly. I recommend that you dump your current support package and install arduino-tiny instead.

Answer 2

Having struggled through this myself, I can confirm that Joel's solution works.

There are quite a lot of posts around that suggests that you can't get the Manchester to work with Arduino1.0x and you need 0020. But you can.

The key is to use the arduino-tiny from the link above, put the tiny folder which you get from there in /hardware and then rename it to attiny and “prospective boards” to boards.

I realise that this doesn’t say any more than Joel already has, but there is so much conflicting and contradictory information around I thought it would be worth adding in my experience

Answer 3

Got the same problem using this lib with a 8 MHz Trinket, but managed to solve it by adding #define __AVR_ATtinyX5__ to the file hardware/attiny/variants/tiny8/pins_arduino.h. I'm using the Adafruit support package for ATtiny. Perhaps a bit of a hack, but I can still build for the UNO, by selecting board in Arduino IDE 1.0.5.