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periph_conf.h File Reference

Configuration of CPU peripherals for SenseBox MCU with SAMD21. More...

Detailed Description

Configuration of CPU peripherals for SenseBox MCU with SAMD21.

Author
Jose Alamos jose..nosp@m.alam.nosp@m.os@ha.nosp@m.w-ha.nosp@m.mburg.nosp@m..de
Leandro Lanzieri leand.nosp@m.ro.l.nosp@m.anzie.nosp@m.ri@h.nosp@m.aw-ha.nosp@m.mbur.nosp@m.g.de

Definition in file periph_conf.h.

#include <stdint.h>
#include "cpu.h"
#include "periph_cpu.h"
+ Include dependency graph for periph_conf.h:
+ This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

External oscillator and clock configuration

For selection of the used CORECLOCK, we have implemented two choices:

  • usage of the PLL fed by the internal 8MHz oscillator divided by 8
  • usage of the internal 8MHz oscillator directly, divided by N if needed

The PLL option allows for the usage of a wider frequency range and a more stable clock with less jitter. This is why we use this option as default.

The target frequency is computed from the PLL multiplier and the PLL divisor. Use the following formula to compute your values:

CORECLOCK = ((PLL_MUL + 1) * 1MHz) / PLL_DIV

NOTE: The PLL circuit does not run with less than 32MHz while the maximum PLL frequency is 96MHz. So PLL_MULL must be between 31 and 95!

The internal Oscillator used directly can lead to a slightly better power efficiency to the cost of a less stable clock. Use this option when you know what you are doing! The actual core frequency is adjusted as follows:

CORECLOCK = 8MHz / DIV

NOTE: A core clock frequency below 1MHz is not recommended

#define CLOCK_USE_PLL   (1)
 
#define CLOCK_DIV   (1U)
 
#define CLOCK_CORECLOCK   (8000000 / CLOCK_DIV)
 

Timer peripheral configuration

#define TIMER_0_MAX_VALUE   0xffff
 
#define TIMER_0_ISR   isr_tc3
 
#define TIMER_1_ISR   isr_tc4
 
#define TIMER_NUMOF   ARRAY_SIZE(timer_config)
 
static const tc32_conf_t timer_config []
 

UART configuration

#define UART_0_ISR   isr_sercom3
 
#define UART_1_ISR   isr_sercom4
 
#define UART_NUMOF   ARRAY_SIZE(uart_config)
 
static const uart_conf_t uart_config []
 

SPI configuration

#define SPI_NUMOF   ARRAY_SIZE(spi_config)
 
static const spi_conf_t spi_config []
 

I2C configuration

#define I2C_NUMOF   ARRAY_SIZE(i2c_config)
 
static const i2c_conf_t i2c_config []
 

RTT configuration

#define RTT_FREQUENCY   (32768U) /* in Hz. For changes see `rtc_rtt.c` */
 

ADC configuration

#define ADC_PRESCALER   ADC_CTRLB_PRESCALER_DIV512
 
#define ADC_NEG_INPUT   ADC_INPUTCTRL_MUXNEG_GND
 
#define ADC_GAIN_FACTOR_DEFAULT   ADC_INPUTCTRL_GAIN_1X
 
#define ADC_REF_DEFAULT   ADC_REFCTRL_REFSEL_INT1V
 
#define ADC_NUMOF   ARRAY_SIZE(adc_channels)
 
static const adc_conf_chan_t adc_channels []
 

USB peripheral configuration

static const sam0_common_usb_config_t sam_usbdev_config []
 

Macro Definition Documentation

◆ ADC_GAIN_FACTOR_DEFAULT

#define ADC_GAIN_FACTOR_DEFAULT   ADC_INPUTCTRL_GAIN_1X

Definition at line 232 of file periph_conf.h.

◆ ADC_NEG_INPUT

#define ADC_NEG_INPUT   ADC_INPUTCTRL_MUXNEG_GND

Definition at line 231 of file periph_conf.h.

◆ ADC_NUMOF

#define ADC_NUMOF   ARRAY_SIZE(adc_channels)

Definition at line 246 of file periph_conf.h.

◆ ADC_PRESCALER

#define ADC_PRESCALER   ADC_CTRLB_PRESCALER_DIV512

Definition at line 229 of file periph_conf.h.

◆ ADC_REF_DEFAULT

#define ADC_REF_DEFAULT   ADC_REFCTRL_REFSEL_INT1V

Definition at line 233 of file periph_conf.h.

◆ CLOCK_CORECLOCK

#define CLOCK_CORECLOCK   (8000000 / CLOCK_DIV)

Definition at line 74 of file periph_conf.h.

◆ CLOCK_DIV

#define CLOCK_DIV   (1U)

Definition at line 72 of file periph_conf.h.

◆ CLOCK_USE_PLL

#define CLOCK_USE_PLL   (1)

Definition at line 63 of file periph_conf.h.

◆ I2C_NUMOF

#define I2C_NUMOF   ARRAY_SIZE(i2c_config)

Definition at line 211 of file periph_conf.h.

◆ RTT_FREQUENCY

#define RTT_FREQUENCY   (32768U) /* in Hz. For changes see `rtc_rtt.c` */

Definition at line 219 of file periph_conf.h.

◆ SPI_NUMOF

#define SPI_NUMOF   ARRAY_SIZE(spi_config)

Definition at line 183 of file periph_conf.h.

◆ TIMER_0_ISR

#define TIMER_0_ISR   isr_tc3

Definition at line 112 of file periph_conf.h.

◆ TIMER_0_MAX_VALUE

#define TIMER_0_MAX_VALUE   0xffff

Definition at line 109 of file periph_conf.h.

◆ TIMER_1_ISR

#define TIMER_1_ISR   isr_tc4

Definition at line 113 of file periph_conf.h.

◆ TIMER_NUMOF

#define TIMER_NUMOF   ARRAY_SIZE(timer_config)

Definition at line 115 of file periph_conf.h.

◆ UART_0_ISR

#define UART_0_ISR   isr_sercom3

Definition at line 154 of file periph_conf.h.

◆ UART_1_ISR

#define UART_1_ISR   isr_sercom4

Definition at line 155 of file periph_conf.h.

◆ UART_NUMOF

#define UART_NUMOF   ARRAY_SIZE(uart_config)

Definition at line 157 of file periph_conf.h.

Variable Documentation

◆ adc_channels

const adc_conf_chan_t adc_channels[]
static
Initial value:
= {
{ .inputctrl = ADC_INPUTCTRL_MUXPOS_PA04 },
{ .inputctrl = ADC_INPUTCTRL_MUXPOS_PA05 },
{ .inputctrl = ADC_INPUTCTRL_MUXPOS_PA06 },
{ .inputctrl = ADC_INPUTCTRL_MUXPOS_PA07 },
{ .inputctrl = ADC_INPUTCTRL_MUXPOS_PA03 },
{ .inputctrl = ADC_INPUTCTRL_MUXPOS_PA02 },
}
#define ADC_INPUTCTRL_MUXPOS_PA05
Alias for PIN5.
Definition periph_cpu.h:124
#define ADC_INPUTCTRL_MUXPOS_PA07
Alias for PIN7.
Definition periph_cpu.h:126
#define ADC_INPUTCTRL_MUXPOS_PA04
Alias for PIN4.
Definition periph_cpu.h:123
#define ADC_INPUTCTRL_MUXPOS_PA06
Alias for PIN6.
Definition periph_cpu.h:125
#define ADC_INPUTCTRL_MUXPOS_PA02
ADC pin aliases.
Definition periph_cpu.h:119
#define ADC_INPUTCTRL_MUXPOS_PA03
Alias for PIN1.
Definition periph_cpu.h:120

Definition at line 236 of file periph_conf.h.

◆ i2c_config

const i2c_conf_t i2c_config[]
static
Initial value:
= {
{
.dev = &(SERCOM0->I2CM),
.speed = I2C_SPEED_NORMAL,
.scl_pin = GPIO_PIN(PA, 8),
.sda_pin = GPIO_PIN(PA, 9),
.mux = GPIO_MUX_C,
.gclk_src = SAM0_GCLK_MAIN,
.flags = I2C_FLAG_NONE
},
{
.dev = &(SERCOM2->I2CM),
.speed = I2C_SPEED_NORMAL,
.scl_pin = GPIO_PIN(PA, 12),
.sda_pin = GPIO_PIN(PA, 13),
.mux = GPIO_MUX_C,
.gclk_src = SAM0_GCLK_MAIN,
.flags = I2C_FLAG_NONE
}
}
#define GPIO_PIN(x, y)
Define a CPU specific GPIO pin generator macro.
Definition periph_cpu.h:46
@ I2C_SPEED_NORMAL
normal mode: ~100 kbit/s
Definition periph_cpu.h:278
@ PA
port A
@ I2C_FLAG_NONE
No flags set.
@ GPIO_MUX_C
select peripheral function C
#define SAM0_GCLK_MAIN
120 MHz main clock
Definition periph_cpu.h:74

Definition at line 190 of file periph_conf.h.

◆ sam_usbdev_config

const sam0_common_usb_config_t sam_usbdev_config[]
static
Initial value:
= {
{
.dm = GPIO_PIN(PA, 24),
.dp = GPIO_PIN(PA, 25),
.d_mux = GPIO_MUX_G,
.device = &USB->DEVICE,
.gclk_src = SAM0_GCLK_MAIN,
}
}
@ GPIO_MUX_G
select peripheral function G

Definition at line 253 of file periph_conf.h.

◆ spi_config

const spi_conf_t spi_config[]
static
Initial value:
= {
{
.dev = &SERCOM1->SPI,
.miso_pin = GPIO_PIN(PA, 19),
.mosi_pin = GPIO_PIN(PA, 16),
.clk_pin = GPIO_PIN(PA, 17),
.miso_mux = GPIO_MUX_C,
.mosi_mux = GPIO_MUX_C,
.clk_mux = GPIO_MUX_C,
.miso_pad = SPI_PAD_MISO_3,
.mosi_pad = SPI_PAD_MOSI_0_SCK_1,
.gclk_src = SAM0_GCLK_MAIN,
}
}
@ SPI_PAD_MISO_3
use pad 3 for MISO line
@ SPI_PAD_MOSI_0_SCK_1
use pad 0 for MOSI, pad 1 for SCK

Definition at line 164 of file periph_conf.h.

◆ timer_config

const tc32_conf_t timer_config[]
static
Initial value:
= {
{
.dev = TC3,
.irq = TC3_IRQn,
.pm_mask = PM_APBCMASK_TC3,
.gclk_ctrl = GCLK_CLKCTRL_ID_TCC2_TC3,
.gclk_src = SAM0_GCLK_MAIN,
.flags = TC_CTRLA_MODE_COUNT16,
},
{
.dev = TC4,
.irq = TC4_IRQn,
.pm_mask = PM_APBCMASK_TC4 | PM_APBCMASK_TC5,
.gclk_ctrl = GCLK_CLKCTRL_ID_TC4_TC5,
.gclk_src = SAM0_GCLK_MAIN,
.flags = TC_CTRLA_MODE_COUNT32,
}
}

Definition at line 82 of file periph_conf.h.

◆ uart_config

const uart_conf_t uart_config[]
static
Initial value:
= {
{
.dev = &SERCOM3->USART,
.rx_pin = GPIO_PIN(PA, 23),
.tx_pin = GPIO_PIN(PA, 22),
.mux = GPIO_MUX_C,
.rx_pad = UART_PAD_RX_1,
.tx_pad = UART_PAD_TX_0,
.flags = UART_FLAG_NONE,
.gclk_src = SAM0_GCLK_MAIN,
},
{
.dev = &SERCOM4->USART,
.rx_pin = GPIO_PIN(PB, 9),
.tx_pin = GPIO_PIN(PB, 8),
.mux = GPIO_MUX_D,
.rx_pad = UART_PAD_RX_1,
.tx_pad = UART_PAD_TX_0,
.flags = UART_FLAG_NONE,
.gclk_src = SAM0_GCLK_MAIN,
}
}
@ UART_PAD_RX_1
select pad 1
@ PB
port B
@ UART_FLAG_NONE
No flags set.
@ UART_PAD_TX_0
select pad 0
@ GPIO_MUX_D
select peripheral function D

Definition at line 122 of file periph_conf.h.