diff options
| -rw-r--r-- | ports/samd/machine_i2c.c | 11 | ||||
| -rw-r--r-- | ports/samd/machine_spi.c | 8 |
2 files changed, 16 insertions, 3 deletions
diff --git a/ports/samd/machine_i2c.c b/ports/samd/machine_i2c.c index d943b6b2f..76d24674f 100644 --- a/ports/samd/machine_i2c.c +++ b/ports/samd/machine_i2c.c @@ -35,7 +35,7 @@ #include "clock_config.h" #define DEFAULT_I2C_FREQ (400000) -#define RISETIME_NS (300) +#define RISETIME_NS (200) #define I2C_TIMEOUT (100) #define IS_BUS_BUSY (i2c->I2CM.STATUS.bit.BUSSTATE == 3) @@ -184,7 +184,14 @@ mp_obj_t machine_i2c_make_new(const mp_obj_type_t *type, size_t n_args, size_t n // baud = peripheral_freq / (2 * baudrate) - 5 - (rise_time * peripheral_freq) / 2 // Just set the minimal configuration for standard and fast mode. // Set Baud. Assume ~300ns rise time. Maybe set later by a keyword argument. - i2c->I2CM.BAUD.reg = get_peripheral_freq() / (2 * self->freq) - 5 - (get_peripheral_freq() / 1000000) * RISETIME_NS / 2000; + int32_t baud = get_peripheral_freq() / (2 * self->freq) - 5 - (get_peripheral_freq() / 1000000) * RISETIME_NS / 2000; + if (baud < 0) { + baud = 0; + } + if (baud > 255) { + baud = 255; + } + i2c->I2CM.BAUD.reg = baud; // Enable interrupts sercom_register_irq(self->id, &common_i2c_irq_handler); diff --git a/ports/samd/machine_spi.c b/ports/samd/machine_spi.c index 4ffc7095c..d2cdf2cd4 100644 --- a/ports/samd/machine_spi.c +++ b/ports/samd/machine_spi.c @@ -208,7 +208,13 @@ STATIC void machine_spi_init(mp_obj_base_t *self_in, size_t n_args, const mp_obj // SPI is driven by the clock of GCLK Generator 2, freq by get_peripheral_freq() // baud = bus_freq / (2 * baudrate) - 1 - uint32_t baud = get_peripheral_freq() / (2 * self->baudrate) - 1; + uint32_t baud = get_peripheral_freq() / (2 * self->baudrate); + if (baud > 0) { // Avoid underflow + baud -= 1; + } + if (baud > 255) { // Avoid overflow + baud = 255; + } spi->SPI.BAUD.reg = baud; // Set Baud // Enable RXC interrupt only if miso is defined |