Commit 7343085d authored by Birte Kristina Friesel's avatar Birte Kristina Friesel
Browse files

Blinkenrocket: Configurable I2C speed

parent 720d72a7

src/arch/blinkenrocket/Makefile.inc

+4 −0
Original line number Diff line number Diff line
@@ -27,6 +27,10 @@ else ifneq ($(findstring i2c,${arch_drivers}), ) 
	TARGETS += src/arch/blinkenrocket/driver/i2c.cc

endif



ifneq (${i2c_freq}, )

	COMMON_FLAGS += -DF_I2C=${i2c_freq}

endif



OBJECTS = ${TARGETS:.cc=.o}



.cc.o:

src/arch/blinkenrocket/driver/i2c.cc

+6 −2
Original line number Diff line number Diff line
@@ -3,6 +3,10 @@ 
#include <avr/io.h>

#include <avr/interrupt.h>



#ifndef F_I2C

#define F_I2C 100000UL

#endif



inline void await_twint(unsigned char twcr_values)

{

#if 1
@@ -27,7 +31,7 @@ static signed char i2c_start_read(unsigned char addr) 
	if (!(TWSR & 0x18)) // 0x08 == START ok, 0x10 == RESTART ok

		return -1;



	// Note: An adress with read bit set ("... | 1") causes the TWI momodule

	// Note: An adress with read bit set ("... | 1") causes the TWI module

	// to switch to Master Receive mode

	TWDR = (addr << 1) | 1;

	await_twint(_BV(TWEN));
@@ -106,7 +110,7 @@ static signed char i2c_receive(uint8_t len, uint8_t *data) 
signed char I2C::setup()

{

	TWSR = 0;

	TWBR = ((F_CPU / 100000UL) - 16) / 2;

	TWBR = ((F_CPU / F_I2C) - 16) / 2;



	return 0;

}