i2c fixed

firmware/slavechip/i2c_simple.c

@@ -2,14 +2,30 @@
 #include <avr/io.h>
 #include <avr/pgmspace.h>
 #include <util/twi.h>
+#include <util/delay.h>
 
 #include "i2c_simple.h"
+#include "debug.h"
+
+//#define I2C_WAIT() while(!(TWCR & _BV(TWINT)))
+#define I2C_WAIT() i2c_wait();
+
+
+void inline i2c_wait(){
+	uint16_t cntr=0;
+	while(!(TWCR & _BV(TWINT))){
+		cntr++;
+		if(cntr >= 1000){
+			dbgLog("i2c waittime exceeded!\n");
+		}
+	}
+}
+
 
-#define I2C_WAIT() while(!(TWCR & _BV(TWINT)))
 
 void i2c_init()
 {
-	TWBR = 32;//bit rate
+	TWBR = 32;//bit rate: 100kbit
 	TWSR = 0;//Prescaler
 	
 //	TWAR = 0x80;//our address 1000 000, don't listen to general call
@@ -53,6 +69,7 @@ uint8_t i2c_read(uint8_t addr, uint8_t len, uint8_t *data)
 	data[done] = TWDR;
 	done++;
 	TWCR |= _BV(TWINT) | _BV(TWSTO);
+	_delay_us(20); // wait about 2 bit periods
 	return done;
 }
 
@@ -91,6 +108,7 @@ uint8_t i2c_write_i(uint8_t addr, uint8_t len, uint8_t *data, uint8_t stop)
 	}
 	
 	if(stop) {TWCR |= _BV(TWINT) | _BV(TWSTO);}
+	_delay_us(20); // wait about 2 bit periods
 	return done;
 }