h3n3/klipper
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

avr: Allow I2C bus speed to be set by Klipper (#6111)

Browse Source 
Allow I2C bus speed to be set by appropriate Klipper commands.

Signed-off-by: Matthew Swabey <matthew@swabey.org>
This commit is contained in:
Dr. Matthew Swabey
2023-03-21 15:02:58 -04:00
committed by GitHub
parent e2d7c59812
commit 2466b7a2c6
2 changed files with 24 additions and 28 deletions
Download Patch File Download Diff File Expand all files Collapse all files

36
src/avr/i2c.c
View File

@@ -27,31 +27,27 @@ static const uint8_t SCL = GPIO('D', 0), SDA = GPIO('D', 1);
DECL_CONSTANT_STR("BUS_PINS_twi", "PD0,PD1");
#endif
static void
i2c_init(void)
{
if (TWCR & (1<<TWEN))
// Already setup
return;
// Setup output pins and enable pullups
gpio_out_setup(SDA, 1);
gpio_out_setup(SCL, 1);
// Set 100Khz frequency
TWSR = 0;
TWBR = ((CONFIG_CLOCK_FREQ / 100000) - 16) / 2;
// Enable interface
TWCR = (1<<TWEN);
}
struct i2c_config
i2c_setup(uint32_t bus, uint32_t rate, uint8_t addr)
{
if (bus)
shutdown("Unsupported i2c bus");
i2c_init();
if (!(TWCR & (1<<TWEN))) {
// Setup output pins and enable pullups
gpio_out_setup(SDA, 1);
gpio_out_setup(SCL, 1);
// Set frequency avoiding pulling in integer divide
TWSR = 0;
if (rate >= 400000)
TWBR = ((CONFIG_CLOCK_FREQ / 400000) - 16) / 2;
else
TWBR = ((CONFIG_CLOCK_FREQ / 100000) - 16) / 2;
// Enable interface
TWCR = (1<<TWEN);
}
return (struct i2c_config){ .addr=addr<<1 };
}