diff options
| author | Daniel Friesel <derf@finalrewind.org> | 2018-08-16 09:14:56 +0200 |
|---|---|---|
| committer | Daniel Friesel <derf@finalrewind.org> | 2018-08-16 09:14:56 +0200 |
| commit | 7343085df78d0fabedcdd69b207b2c04962cf98a (patch) | |
| tree | 33f7e530f45253826512195df82f721d30033c9e | |
| parent | 720d72a7dc083835475f6cd3e82a1800d43a6671 (diff) | |
Blinkenrocket: Configurable I2C speed
| -rw-r--r-- | src/arch/blinkenrocket/Makefile.inc | 4 | ||||
| -rw-r--r-- | src/arch/blinkenrocket/driver/i2c.cc | 8 |
2 files changed, 10 insertions, 2 deletions
diff --git a/src/arch/blinkenrocket/Makefile.inc b/src/arch/blinkenrocket/Makefile.inc index 1d99d0b..5a4259f 100644 --- a/src/arch/blinkenrocket/Makefile.inc +++ b/src/arch/blinkenrocket/Makefile.inc @@ -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: diff --git a/src/arch/blinkenrocket/driver/i2c.cc b/src/arch/blinkenrocket/driver/i2c.cc index 487c60e..df275ff 100644 --- a/src/arch/blinkenrocket/driver/i2c.cc +++ b/src/arch/blinkenrocket/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) { #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; } |