attiny forgotten bits

flotsam/avr/attiny85/i2c_master.cpp

+//#define F_CPU 1200000UL
+
+#include <avr/io.h>
+#include <util/delay.h>
+#include "tinywirem/TinyWireM.h"                  // I2C Master lib for ATTinys which use USI
+
+typedef unsigned char u8;
+typedef unsigned int u32;
+
+#define LED PB1
+
+void set_led_state(u8 s)
+{
+    if (s) PORTB|=_BV(LED);
+    else PORTB&=~_BV(LED);
+}
+
+int main(void)
+{
+    sei();
+
+    DDRB = 0x00;
+    DDRB |= _BV( LED );
+    
+   
+    TinyWireM.begin();
+
+    u32 led_counter = 0;
+    
+    while(1) {
+        TinyWireM.requestFrom(0x32,1); // Request 1 byte from slave
+        u8 t = TinyWireM.receive();          // get the temperature
+        
+        set_led_state((led_counter++)%2);
+
+        _delay_ms(1000);
+    } 
+}
+

flotsam/avr/attiny85/make_old

+avr-gcc -DAVR -Wall -Os -mmcu=attiny85 -o i2c.elf i2c.c usi_i2c_slave.c
+avr-objcopy --output-target=ihex i2c.elf i2c.ihex
+avrdude -c usbtiny -p t85 -e -U flash:w:i2c.ihex -U lfuse:w:0xE2:m