ATTiny85 I2C library - wire.h / tinyWireM.h / tinyWireS.h

Projects Programming
1

Hi all, after some searching, it's time to ask for some up-to-date advice on this, to save hours of going round in circles.

IDE version 1.8.19
Linux Mint 20
Arduino UNO as ISP as shown on my site.

I am trying to set up 3x ATTiny85 IC's (slaves) to talk to one ATMEGA328P (master / controller) via I2C. Each slave shall have its own unique address (above 7).

So far I have a little test program set up to just use the ATTiny85 to read an analogue input value and send it to the master. I have not yet worked on the master, but am just trying to verify and compile the ATTiny85 code. (This is before getting to pressing upload and using the ISP).

#include <Wire.h>

int inputPin = 5;               // pin PB5 is physical pin 1
int inputValue = 0;

void setup() {
  Wire.begin(8);                // I2C address 8
  Wire.onRequest(requestEvent);
  pinMode(inputPin, INPUT);
}

void loop() {
  inputValue = readInput;
}

int readInput() {
  int inputReadVal = analogRead(inputPin);
  return inputReadVal;
}

int requestEvent() {            // When data is requestd, send the value
  Wire.write(inputValue);
}

I started off with wire.h, but this threw errors for the ATTiny85, so am looking at alternative libraries.

Arduino: 1.8.19 (Linux), Board: "ATtiny25/45/85, ATtiny85, Internal 8 MHz"











/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c: In function 'twi_init':
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:88:16: error: 'SDA' undeclared (first use in this function)
   digitalWrite(SDA, 1);
                ^~~
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:88:16: note: each undeclared identifier is reported only once for each function it appears in
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:89:16: error: 'SCL' undeclared (first use in this function); did you mean 'SPL'?
   digitalWrite(SCL, 1);
                ^~~
                SPL
In file included from /home/scott/.arduino15/packages/arduino/tools/avr-gcc/7.3.0-atmel3.6.1-arduino7/avr/include/avr/io.h:99:0,
                 from /home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:26:
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:92:7: error: 'TWSR' undeclared (first use in this function); did you mean 'ACSR'?
   cbi(TWSR, TWPS0);
       ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:92:3: note: in expansion of macro 'cbi'
   cbi(TWSR, TWPS0);
   ^~~
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:92:13: error: 'TWPS0' undeclared (first use in this function); did you mean 'TWSR'?
   cbi(TWSR, TWPS0);
             ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:92:3: note: in expansion of macro 'cbi'
   cbi(TWSR, TWPS0);
   ^~~
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:93:13: error: 'TWPS1' undeclared (first use in this function); did you mean 'TWPS0'?
   cbi(TWSR, TWPS1);
             ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:93:3: note: in expansion of macro 'cbi'
   cbi(TWSR, TWPS1);
   ^~~
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:94:3: error: 'TWBR' undeclared (first use in this function); did you mean 'TWSR'?
   TWBR = ((F_CPU / TWI_FREQ) - 16) / 2;
   ^~~~
   TWSR
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:102:3: error: 'TWCR' undeclared (first use in this function); did you mean 'TWBR'?
   TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWEA);
   ^~~~
   TWBR
In file included from /home/scott/.arduino15/packages/arduino/tools/avr-gcc/7.3.0-atmel3.6.1-arduino7/avr/include/avr/io.h:99:0,
                 from /home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:26:
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:102:14: error: 'TWEN' undeclared (first use in this function); did you mean 'TWCR'?
   TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWEA);
              ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:102:26: error: 'TWIE' undeclared (first use in this function); did you mean 'TWEN'?
   TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWEA);
                          ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:102:38: error: 'TWEA' undeclared (first use in this function); did you mean 'TWEN'?
   TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWEA);
                                      ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c: In function 'twi_disable':
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:114:3: error: 'TWCR' undeclared (first use in this function); did you mean 'EECR'?
   TWCR &= ~(_BV(TWEN) | _BV(TWIE) | _BV(TWEA));
   ^~~~
   EECR
In file included from /home/scott/.arduino15/packages/arduino/tools/avr-gcc/7.3.0-atmel3.6.1-arduino7/avr/include/avr/io.h:99:0,
                 from /home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:26:
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:114:17: error: 'TWEN' undeclared (first use in this function); did you mean 'TWCR'?
   TWCR &= ~(_BV(TWEN) | _BV(TWIE) | _BV(TWEA));
                 ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:114:29: error: 'TWIE' undeclared (first use in this function); did you mean 'TWEN'?
   TWCR &= ~(_BV(TWEN) | _BV(TWIE) | _BV(TWEA));
                             ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:114:41: error: 'TWEA' undeclared (first use in this function); did you mean 'TWEN'?
   TWCR &= ~(_BV(TWEN) | _BV(TWIE) | _BV(TWEA));
                                         ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:117:16: error: 'SDA' undeclared (first use in this function)
   digitalWrite(SDA, 0);
                ^~~
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:118:16: error: 'SCL' undeclared (first use in this function); did you mean 'SPL'?
   digitalWrite(SCL, 0);
                ^~~
                SPL
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c: In function 'twi_setAddress':
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:130:3: error: 'TWAR' undeclared (first use in this function); did you mean 'TIFR'?
   TWAR = address << 1;
   ^~~~
   TIFR
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c: In function 'twi_setFrequency':
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:141:3: error: 'TWBR' undeclared (first use in this function); did you mean 'TIFR'?
   TWBR = ((F_CPU / frequency) - 16) / 2;
   ^~~~
   TIFR
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c: In function 'twi_readFrom':
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:204:7: error: 'TWDR' undeclared (first use in this function); did you mean 'DWDR'?
       TWDR = twi_slarw;
       ^~~~
       DWDR
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:209:13: error: 'TWCR' undeclared (first use in this function); did you mean 'TWDR'?
     } while(TWCR & _BV(TWWC));
             ^~~~
             TWDR
In file included from /home/scott/.arduino15/packages/arduino/tools/avr-gcc/7.3.0-atmel3.6.1-arduino7/avr/include/avr/io.h:99:0,
                 from /home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:26:
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:209:24: error: 'TWWC' undeclared (first use in this function); did you mean 'TWCR'?
     } while(TWCR & _BV(TWWC));
                        ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:210:16: error: 'TWINT' undeclared (first use in this function)
     TWCR = _BV(TWINT) | _BV(TWEA) | _BV(TWEN) | _BV(TWIE); // enable INTs, but not START
                ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:210:29: error: 'TWEA' undeclared (first use in this function); did you mean 'TWWC'?
     TWCR = _BV(TWINT) | _BV(TWEA) | _BV(TWEN) | _BV(TWIE); // enable INTs, but not START
                             ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:210:41: error: 'TWEN' undeclared (first use in this function); did you mean 'TWEA'?
     TWCR = _BV(TWINT) | _BV(TWEA) | _BV(TWEN) | _BV(TWIE); // enable INTs, but not START
                                         ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:210:53: error: 'TWIE' undeclared (first use in this function); did you mean 'TWEN'?
     TWCR = _BV(TWINT) | _BV(TWEA) | _BV(TWEN) | _BV(TWIE); // enable INTs, but not START
                                                     ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:213:65: error: 'TWSTA' undeclared (first use in this function); did you mean 'TWEA'?
     TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWEA) | _BV(TWINT) | _BV(TWSTA);
                                                                 ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c: In function 'twi_writeTo':
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:301:7: error: 'TWDR' undeclared (first use in this function); did you mean 'DWDR'?
       TWDR = twi_slarw;
       ^~~~
       DWDR
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:306:13: error: 'TWCR' undeclared (first use in this function); did you mean 'TWDR'?
     } while(TWCR & _BV(TWWC));
             ^~~~
             TWDR
In file included from /home/scott/.arduino15/packages/arduino/tools/avr-gcc/7.3.0-atmel3.6.1-arduino7/avr/include/avr/io.h:99:0,
                 from /home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:26:
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:306:24: error: 'TWWC' undeclared (first use in this function); did you mean 'TWCR'?
     } while(TWCR & _BV(TWWC));
                        ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:307:16: error: 'TWINT' undeclared (first use in this function)
     TWCR = _BV(TWINT) | _BV(TWEA) | _BV(TWEN) | _BV(TWIE); // enable INTs, but not START
                ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:307:29: error: 'TWEA' undeclared (first use in this function); did you mean 'TWWC'?
     TWCR = _BV(TWINT) | _BV(TWEA) | _BV(TWEN) | _BV(TWIE); // enable INTs, but not START
                             ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:307:41: error: 'TWEN' undeclared (first use in this function); did you mean 'TWEA'?
     TWCR = _BV(TWINT) | _BV(TWEA) | _BV(TWEN) | _BV(TWIE); // enable INTs, but not START
                                         ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:307:53: error: 'TWIE' undeclared (first use in this function); did you mean 'TWEN'?
     TWCR = _BV(TWINT) | _BV(TWEA) | _BV(TWEN) | _BV(TWIE); // enable INTs, but not START
                                                     ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:310:65: error: 'TWSTA' undeclared (first use in this function); did you mean 'TWEA'?
     TWCR = _BV(TWINT) | _BV(TWEA) | _BV(TWEN) | _BV(TWIE) | _BV(TWSTA); // enable INTs
                                                                 ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c: In function 'twi_reply':
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:397:5: error: 'TWCR' undeclared (first use in this function); did you mean 'EECR'?
     TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWINT) | _BV(TWEA);
     ^~~~
     EECR
In file included from /home/scott/.arduino15/packages/arduino/tools/avr-gcc/7.3.0-atmel3.6.1-arduino7/avr/include/avr/io.h:99:0,
                 from /home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:26:
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:397:16: error: 'TWEN' undeclared (first use in this function); did you mean 'TWCR'?
     TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWINT) | _BV(TWEA);
                ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:397:28: error: 'TWIE' undeclared (first use in this function); did you mean 'TWEN'?
     TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWINT) | _BV(TWEA);
                            ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:397:40: error: 'TWINT' undeclared (first use in this function); did you mean 'TWIE'?
     TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWINT) | _BV(TWEA);
                                        ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:397:53: error: 'TWEA' undeclared (first use in this function); did you mean 'TWEN'?
     TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWINT) | _BV(TWEA);
                                                     ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c: In function 'twi_stop':
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:412:3: error: 'TWCR' undeclared (first use in this function); did you mean 'EECR'?
   TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWEA) | _BV(TWINT) | _BV(TWSTO);
   ^~~~
   EECR
In file included from /home/scott/.arduino15/packages/arduino/tools/avr-gcc/7.3.0-atmel3.6.1-arduino7/avr/include/avr/io.h:99:0,
                 from /home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:26:
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:412:14: error: 'TWEN' undeclared (first use in this function); did you mean 'TWCR'?
   TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWEA) | _BV(TWINT) | _BV(TWSTO);
              ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:412:26: error: 'TWIE' undeclared (first use in this function); did you mean 'TWEN'?
   TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWEA) | _BV(TWINT) | _BV(TWSTO);
                          ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:412:38: error: 'TWEA' undeclared (first use in this function); did you mean 'TWEN'?
   TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWEA) | _BV(TWINT) | _BV(TWSTO);
                                      ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:412:50: error: 'TWINT' undeclared (first use in this function); did you mean 'TWIE'?
   TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWEA) | _BV(TWINT) | _BV(TWSTO);
                                                  ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:412:63: error: 'TWSTO' undeclared (first use in this function)
   TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWEA) | _BV(TWINT) | _BV(TWSTO);
                                                               ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c: In function 'twi_releaseBus':
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:444:3: error: 'TWCR' undeclared (first use in this function); did you mean 'EECR'?
   TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWEA) | _BV(TWINT);
   ^~~~
   EECR
In file included from /home/scott/.arduino15/packages/arduino/tools/avr-gcc/7.3.0-atmel3.6.1-arduino7/avr/include/avr/io.h:99:0,
                 from /home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:26:
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:444:14: error: 'TWEN' undeclared (first use in this function); did you mean 'TWCR'?
   TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWEA) | _BV(TWINT);
              ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:444:26: error: 'TWIE' undeclared (first use in this function); did you mean 'TWEN'?
   TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWEA) | _BV(TWINT);
                          ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:444:38: error: 'TWEA' undeclared (first use in this function); did you mean 'TWEN'?
   TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWEA) | _BV(TWINT);
                                      ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:444:50: error: 'TWINT' undeclared (first use in this function); did you mean 'TWIE'?
   TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWEA) | _BV(TWINT);
                                                  ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c: In function 'twi_handleTimeout':
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:475:29: error: 'TWBR' undeclared (first use in this function); did you mean 'TIFR'?
     uint8_t previous_TWBR = TWBR;
                             ^~~~
                             TIFR
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:476:29: error: 'TWAR' undeclared (first use in this function); did you mean 'TWBR'?
     uint8_t previous_TWAR = TWAR;
                             ^~~~
                             TWBR
In file included from /home/scott/.arduino15/packages/arduino/tools/avr-gcc/7.3.0-atmel3.6.1-arduino7/avr/include/compat/twi.h:36:0,
                 from /home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:29:
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c: In function 'TWI_vect':
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:505:10: error: 'TWSR' undeclared (first use in this function); did you mean 'ACSR'?
   switch(TW_STATUS){
          ^
In file included from /home/scott/.arduino15/packages/arduino/tools/avr-gcc/7.3.0-atmel3.6.1-arduino7/avr/include/avr/io.h:99:0,
                 from /home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:26:
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:505:10: error: 'TWS7' undeclared (first use in this function); did you mean 'TWSR'?
   switch(TW_STATUS){
          ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:505:10: error: 'TWS6' undeclared (first use in this function); did you mean 'TWS7'?
   switch(TW_STATUS){
          ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:505:10: error: 'TWS5' undeclared (first use in this function); did you mean 'TWS6'?
   switch(TW_STATUS){
          ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:505:10: error: 'TWS4' undeclared (first use in this function); did you mean 'TWS5'?
   switch(TW_STATUS){
          ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:505:10: error: 'TWS3' undeclared (first use in this function); did you mean 'TWS4'?
   switch(TW_STATUS){
          ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:510:7: error: 'TWDR' undeclared (first use in this function); did you mean 'TWSR'?
       TWDR = twi_slarw;
       ^~~~
       TWSR
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:530:10: error: 'TWCR' undeclared (first use in this function); did you mean 'TWDR'?
          TWCR = _BV(TWINT) | _BV(TWSTA)| _BV(TWEN) ;
          ^~~~
          TWDR
In file included from /home/scott/.arduino15/packages/arduino/tools/avr-gcc/7.3.0-atmel3.6.1-arduino7/avr/include/avr/io.h:99:0,
                 from /home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:26:
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:530:21: error: 'TWINT' undeclared (first use in this function)
          TWCR = _BV(TWINT) | _BV(TWSTA)| _BV(TWEN) ;
                     ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:530:34: error: 'TWSTA' undeclared (first use in this function); did you mean 'TWS3'?
          TWCR = _BV(TWINT) | _BV(TWSTA)| _BV(TWEN) ;
                                  ^
/home/scott/.arduino15/packages/arduino/hardware/avr/1.8.5/libraries/Wire/src/utility/twi.c:530:46: error: 'TWEN' undeclared (first use in this function); did you mean 'TWINT'?
          TWCR = _BV(TWINT) | _BV(TWSTA)| _BV(TWEN) ;
                                              ^
exit status 1
Error compiling for board ATtiny25/45/85.


This report would have more information with
"Show verbose output during compilation"
option enabled in File -> Preferences.

I can find tinyWireM.h which appears to be for the master/controller, not the slave device. I have found this installed in the IDE, and in the menu to add to a sketch. Here it is on the Adafruit Github page.

There is mention on stack exchange about there being a tinyWireS.h slave library too, but this is not included in the IDE list, nor can I find it in Adafruits github repo.

If tinyWireS.h is the solution for me, can someone say where to find the latest/stable/ideal release?
OR
Is there a better library to use for this?
OR
Is there a better method of making these boards communicate?

Many thanks, Scott.

2

If you use the ATTinyCore core you can use (a version of) the Wire library. You will need to use the default pins for I2C, pin 0 (physical pin 5) = SDA and pin 2 (physical pin 7) = SCL. See the I2C, SPI and Serial section.

image
image1920×402 56.5 KB

When learning to program my tiny85 projects I tried many cores and the ATTinyCore code is simply the best. It is certainly the best documented.

3

Genius!!

Thanks @groundFungus !! Installing ATTinyCore on my IDE has fixed it! Now there are no verification errors.

I didn't know what a core was until today, every day's a school day!

However, This has now caused me a different headache using my UNO ISP to upload to the ATTiny85 IC, but I am in the process of building a direct USB programmer, so hopefully I should overcome that soon enough.

Cheers, Scott.