diff options
| author | Daniel Friesel <derf@finalrewind.org> | 2018-08-16 12:58:24 +0200 |
|---|---|---|
| committer | Daniel Friesel <derf@finalrewind.org> | 2018-08-16 12:58:24 +0200 |
| commit | f6972a43581b24281b322a6f8d2bf02dafbe4433 (patch) | |
| tree | 7ab50ae57739d8df9cc4a898b80c8b5c4ba9ceee /src/arch | |
| parent | 7343085df78d0fabedcdd69b207b2c04962cf98a (diff) | |
configurable i2c bitrate on arduino nano
Diffstat (limited to 'src/arch')
| -rw-r--r-- | src/arch/arduino-nano/Makefile.inc | 4 | ||||
| -rw-r--r-- | src/arch/arduino-nano/driver/i2c.cc | 6 |
2 files changed, 9 insertions, 1 deletions
diff --git a/src/arch/arduino-nano/Makefile.inc b/src/arch/arduino-nano/Makefile.inc index d481fa2..18a6563 100644 --- a/src/arch/arduino-nano/Makefile.inc +++ b/src/arch/arduino-nano/Makefile.inc @@ -32,6 +32,10 @@ ifneq ($(findstring stdin,${arch_drivers}), ) TARGETS += src/arch/arduino-nano/driver/stdin.cc endif +ifneq (${i2c_freq}, ) + COMMON_FLAGS += -DF_I2C=${i2c_freq} +endif + OBJECTS = ${TARGETS:.cc=.o} .cc.o: diff --git a/src/arch/arduino-nano/driver/i2c.cc b/src/arch/arduino-nano/driver/i2c.cc index cfbea59..0a2f595 100644 --- a/src/arch/arduino-nano/driver/i2c.cc +++ b/src/arch/arduino-nano/driver/i2c.cc @@ -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) { TWCR = twcr_values | _BV(TWINT) | _BV(TWIE); @@ -99,7 +103,7 @@ 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; } |