void cc2538_i2c_init_master(uint32_t speed_hz)
{
SYS_CTRL_RCGCI2C |= 1; /**< Enable the I2C0 clock. */
SYS_CTRL_SCGCI2C |= 1; /**< Enable the I2C0 clock. */
SYS_CTRL_DCGCI2C |= 1; /**< Enable the I2C0 clock. */
/* Reset I2C peripheral */
SYS_CTRL_SRI2C |= 1;
#ifdef MODULE_XTIMER
xtimer_usleep(50);
#else
thread_yield();
#endif
SYS_CTRL_SRI2C &= ~1;
/* Clear all pin override flags except PUE (Pull-Up Enable) */
IOC_PXX_OVER[I2C_0_SCL_PIN] &= IOC_OVERRIDE_PUE;
IOC_PXX_OVER[I2C_0_SDA_PIN] &= IOC_OVERRIDE_PUE;
IOC_PXX_SEL[I2C_0_SCL_PIN] = I2C_CMSSCL;
IOC_PXX_SEL[I2C_0_SDA_PIN] = I2C_CMSSDA;
IOC_I2CMSSCL = I2C_0_SCL_PIN;
IOC_I2CMSSDA = I2C_0_SDA_PIN;
gpio_hardware_control(I2C_0_SCL_PIN);
gpio_hardware_control(I2C_0_SDA_PIN);
/* Initialize the I2C master by setting the Master Function Enable bit */
I2CM_CR |= MFE;
/* Set the SCL clock speed */
uint32_t ps = sys_clock_freq();
uint32_t denom = 2 * (SCL_LP + SCL_HP) * speed_hz;
ps += denom / 2;
ps /= denom;
I2CM_TPR = ps - 1;
/* Enable I2C master interrupts */
NVIC_SetPriority(I2C_IRQn, I2C_IRQ_PRIO);
NVIC_EnableIRQ(I2C_IRQn);
i2cm_ctrl_write(STOP);
/* Enable I2C master interrupts */
I2CM_IMR = 1;
}
static void recover_i2c_bus(void) {
/* Switch to software GPIO mode for bus recovery */
release_sda();
release_scl();
if (!bus_quiet()) {
const uint_fast8_t try_limit = 200;
uint_fast8_t n;
for (n = 0; n < try_limit; n++) {
if (bus_quiet()) {
DEBUG("%s(): SDA released after%4u SCL pulses.\n", __FUNCTION__, n);
break;
}
assert_scl();
#ifdef MODULE_XTIMER
xtimer_usleep(scl_delay);
#else
thread_yield();
#endif
release_scl();
#ifdef MODULE_XTIMER
xtimer_usleep(scl_delay);
#else
thread_yield();
#endif
}
if (n >= try_limit) {
DEBUG("%s(): Failed to release SDA after%4u SCL pulses.\n", __FUNCTION__, n);
}
}
/* Return to hardware mode for the I2C pins */
gpio_hardware_control(I2C_0_SCL_PIN);
gpio_hardware_control(I2C_0_SDA_PIN);
}
static int init_base(uart_t uart, uint32_t baudrate)
{
cc2538_uart_t *u = NULL;
switch (uart) {
#if UART_0_EN
case UART_0:
u = UART_0_DEV;
/*
* Select the UARTx RX pin by writing to the IOC_UARTRXD_UARTn register
*/
IOC_UARTRXD_UART0 = UART_0_RX_PIN;
/*
* Pad Control for the TX pin:
* - Set function to UARTn TX
* - Output Enable
*/
IOC_PXX_SEL[UART_0_TX_PIN] = UART0_TXD;
IOC_PXX_OVER[UART_0_TX_PIN] = IOC_OVERRIDE_OE;
/* Set RX and TX pins to peripheral mode */
gpio_hardware_control(UART_0_TX_PIN);
gpio_hardware_control(UART_0_RX_PIN);
break;
#endif
#if UART_1_EN
case UART_1:
u = UART_1_DEV;
/*
* Select the UARTx RX pin by writing to the IOC_UARTRXD_UARTn register
*/
IOC_UARTRXD_UART1 = UART_1_RX_PIN;
/*
* Pad Control for the TX pin:
* - Set function to UARTn TX
* - Output Enable
*/
IOC_PXX_SEL[UART_1_TX_PIN] = UART1_TXD;
IOC_PXX_OVER[UART_1_TX_PIN] = IOC_OVERRIDE_OE;
/* Set RX and TX pins to peripheral mode */
gpio_hardware_control(UART_1_TX_PIN);
gpio_hardware_control(UART_1_RX_PIN);
break;
#endif
default:
(void)u;
return UART_NODEV;
}
#if UART_0_EN || UART_1_EN
/* Enable clock for the UART while Running, in Sleep and Deep Sleep */
unsigned int uart_num = ( (uintptr_t)u - (uintptr_t)UART0 ) / 0x1000;
SYS_CTRL_RCGCUART |= (1 << uart_num);
SYS_CTRL_SCGCUART |= (1 << uart_num);
SYS_CTRL_DCGCUART |= (1 << uart_num);
/* Make sure the UART is disabled before trying to configure it */
u->cc2538_uart_ctl.CTL = 0;
/* Run on SYS_DIV */
u->CC = 0;
/* On the CC2538, hardware flow control is supported only on UART1 */
if (u == UART1) {
#ifdef UART_1_RTS_PIN
IOC_PXX_SEL[UART_1_RTS_PIN] = UART1_RTS;
gpio_hardware_control(UART_1_RTS_PIN);
IOC_PXX_OVER[UART_1_RTS_PIN] = IOC_OVERRIDE_OE;
u->cc2538_uart_ctl.CTLbits.RTSEN = 1;
#endif
#ifdef UART_1_CTS_PIN
IOC_UARTCTS_UART1 = UART_1_CTS_PIN;
gpio_hardware_control(UART_1_CTS_PIN);
IOC_PXX_OVER[UART_1_CTS_PIN] = IOC_OVERRIDE_DIS;
u->cc2538_uart_ctl.CTLbits.CTSEN = 1;
#endif
}
/* Enable clock for the UART while Running, in Sleep and Deep Sleep */
uart_num = ( (uintptr_t)u - (uintptr_t)UART0 ) / 0x1000;
SYS_CTRL_RCGCUART |= (1 << uart_num);
SYS_CTRL_SCGCUART |= (1 << uart_num);
SYS_CTRL_DCGCUART |= (1 << uart_num);
/*
* UART Interrupt Masks:
* Acknowledge RX and RX Timeout
* Acknowledge Framing, Overrun and Break Errors
*/
u->cc2538_uart_im.IM = 0;
u->cc2538_uart_im.IMbits.RXIM = 1; /**< UART receive interrupt mask */
u->cc2538_uart_im.IMbits.RTIM = 1; /**< UART receive time-out interrupt mask */
u->cc2538_uart_im.IMbits.OEIM = 1; /**< UART overrun error interrupt mask */
u->cc2538_uart_im.IMbits.BEIM = 1; /**< UART break error interrupt mask */
u->cc2538_uart_im.IMbits.FEIM = 1; /**< UART framing error interrupt mask */
/* Set FIFO interrupt levels: */
u->cc2538_uart_ifls.IFLSbits.RXIFLSEL = FIFO_LEVEL_4_8TH; /**< MCU default */
u->cc2538_uart_ifls.IFLSbits.TXIFLSEL = FIFO_LEVEL_4_8TH; /**< MCU default */
u->cc2538_uart_ctl.CTLbits.RXE = 1;
u->cc2538_uart_ctl.CTLbits.TXE = 1;
u->cc2538_uart_ctl.CTLbits.HSE = UART_CTL_HSE_VALUE;
/* Set the divisor for the baud rate generator */
uint32_t divisor = sys_clock_freq();
divisor <<= UART_CTL_HSE_VALUE + 2;
divisor += baudrate / 2; /**< Avoid a rounding error */
divisor /= baudrate;
u->IBRD = divisor >> DIVFRAC_NUM_BITS;
u->FBRD = divisor & DIVFRAC_MASK;
/* Configure line control for 8-bit, no parity, 1 stop bit and enable */
u->cc2538_uart_lcrh.LCRH = (WLEN_8_BITS << 5) | FEN;
/* UART Enable */
u->cc2538_uart_ctl.CTLbits.UARTEN = 1;
return UART_OK;
#endif /* UART_0_EN || UART_1_EN */
}
int uart_init_blocking(uart_t uart, uint32_t baudrate)
{
cc2538_uart_t *u;
unsigned int uart_num;
uint32_t divisor;
switch (uart) {
#if UART_0_EN
case UART_0:
u = UART_0_DEV;
/* Run on SYS_DIV */
u->CC = 0;
/*
* Select the UARTx RX pin by writing to the IOC_UARTRXD_UARTn register
*/
IOC_UARTRXD_UART0 = UART_0_RX_PIN;
/*
* Pad Control for the TX pin:
* - Set function to UARTn TX
* - Output Enable
*/
IOC_PXX_SEL[UART_0_TX_PIN] = UART0_TXD;
IOC_PXX_OVER[UART_0_TX_PIN] = IOC_OVERRIDE_OE;
/* Set RX and TX pins to peripheral mode */
gpio_hardware_control(UART_0_TX_PIN);
gpio_hardware_control(UART_0_RX_PIN);
break;
#endif
#if UART_1_EN
case UART_1:
u = UART_1_DEV;
/* Run on SYS_DIV */
u->CC = 0;
/*
* Select the UARTx RX pin by writing to the IOC_UARTRXD_UARTn register
*/
IOC_UARTRXD_UART1 = UART_1_RX_PIN;
/*
* Pad Control for the TX pin:
* - Set function to UARTn TX
* - Output Enable
*/
IOC_PXX_SEL[UART_1_TX_PIN] = UART1_TXD;
IOC_PXX_OVER[UART_1_TX_PIN] = IOC_OVERRIDE_OE;
/* Set RX and TX pins to peripheral mode */
gpio_hardware_control(UART_1_TX_PIN);
gpio_hardware_control(UART_1_RX_PIN);
#if ( defined(UART_1_RTS_PORT) && defined(UART_1_RTS_PIN) )
IOC_PXX_SEL[UART_1_RTS_PIN] = UART1_RTS;
gpio_hardware_control(UART_1_RTS_PIN);
IOC_PXX_OVER[UART_1_RTS_PIN] = IOC_OVERRIDE_OE;
u->CTLbits.RTSEN = 1;
#endif
#if ( defined(UART_1_CTS_PORT) && defined(UART_1_CTS_PIN) )
IOC_UARTCTS_UART1 = UART_1_CTS_PIN;
gpio_hardware_control(UART_1_CTS_PIN);
IOC_PXX_OVER[UART_1_CTS_PIN] = IOC_OVERRIDE_DIS;
u->CTLbits.CTSEN = 1;
#endif
break;
#endif
default:
return -1;
}
/* Enable clock for the UART while Running, in Sleep and Deep Sleep */
uart_num = ( (uintptr_t)u - (uintptr_t)UART0 ) / 0x1000;
SYS_CTRL_RCGCUART |= (1 << uart_num);
SYS_CTRL_SCGCUART |= (1 << uart_num);
SYS_CTRL_DCGCUART |= (1 << uart_num);
/*
* UART Interrupt Masks:
* Acknowledge RX and RX Timeout
* Acknowledge Framing, Overrun and Break Errors
*/
u->IM = 0;
u->IMbits.RXIM = 1; /**< UART receive interrupt mask */
u->IMbits.RTIM = 1; /**< UART receive time-out interrupt mask */
u->IMbits.OEIM = 1; /**< UART overrun error interrupt mask */
u->IMbits.BEIM = 1; /**< UART break error interrupt mask */
u->IMbits.FEIM = 1; /**< UART framing error interrupt mask */
/* Set FIFO interrupt levels: */
u->IFLSbits.RXIFLSEL = FIFO_LEVEL_1_8TH;
u->IFLSbits.TXIFLSEL = FIFO_LEVEL_4_8TH;
/* Make sure the UART is disabled before trying to configure it */
u->CTL = 0;
u->CTLbits.RXE = 1;
u->CTLbits.TXE = 1;
u->CTLbits.HSE = UART_CTL_HSE_VALUE;
/* Set the divisor for the baud rate generator */
divisor = sys_clock_freq();
divisor <<= UART_CTL_HSE_VALUE + 2;
divisor /= baudrate;
u->IBRD = divisor >> DIVFRAC_NUM_BITS;
u->FBRD = divisor & DIVFRAC_MASK;
/* Configure line control for 8-bit, no parity, 1 stop bit and enable */
u->LCRH = 0;
u->LCRHbits.WLEN = UART_WORD_LENGTH - 5;
u->LCRHbits.FEN = 1; /**< Enable FIFOs */
u->LCRHbits.PEN = 0; /**< No parity */
/* UART Enable */
u->CTLbits.UARTEN = 1;
return 0;
}