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TARGET_WALLBOT_BLE/TOOLCHAIN_GCC_ARM/twi_master.h@172:65be27845400, 2019-02-20 (annotated)

Committer:
AnnaBridge
Date:
Wed Feb 20 20:53:29 2019 +0000
Revision:
172:65be27845400
Parent:
171:3a7713b1edbc 
mbed library release version 165

Who changed what in which revision?

UserRevisionLine numberNew contents of line
AnnaBridge 156:ff21514d8981 1 /* Copyright (c) 2009 Nordic Semiconductor. All Rights Reserved.
AnnaBridge 156:ff21514d8981 2 *
AnnaBridge 156:ff21514d8981 3 * The information contained herein is property of Nordic Semiconductor ASA.
AnnaBridge 156:ff21514d8981 4 * Terms and conditions of usage are described in detail in NORDIC
AnnaBridge 156:ff21514d8981 5 * SEMICONDUCTOR STANDARD SOFTWARE LICENSE AGREEMENT.
AnnaBridge 156:ff21514d8981 6 *
AnnaBridge 156:ff21514d8981 7 * Licensees are granted free, non-transferable use of the information. NO
AnnaBridge 156:ff21514d8981 8 * WARRANTY of ANY KIND is provided. This heading must NOT be removed from
AnnaBridge 156:ff21514d8981 9 * the file.
AnnaBridge 156:ff21514d8981 10 *
AnnaBridge 156:ff21514d8981 11 */
AnnaBridge 156:ff21514d8981 12
AnnaBridge 156:ff21514d8981 13 #ifndef TWI_MASTER_H
AnnaBridge 156:ff21514d8981 14 #define TWI_MASTER_H
AnnaBridge 156:ff21514d8981 15
AnnaBridge 156:ff21514d8981 16
AnnaBridge 156:ff21514d8981 17 #ifdef __cplusplus
AnnaBridge 156:ff21514d8981 18 extern "C" {
AnnaBridge 156:ff21514d8981 19 #endif
AnnaBridge 156:ff21514d8981 20
AnnaBridge 156:ff21514d8981 21 /*lint ++flb "Enter library region" */
AnnaBridge 156:ff21514d8981 22
AnnaBridge 156:ff21514d8981 23 #include <stdbool.h>
AnnaBridge 156:ff21514d8981 24 #include <stdint.h>
AnnaBridge 156:ff21514d8981 25
AnnaBridge 156:ff21514d8981 26 #include "nrf51.h"
AnnaBridge 156:ff21514d8981 27
AnnaBridge 156:ff21514d8981 28 /** @file
AnnaBridge 156:ff21514d8981 29 * @brief Software controlled TWI Master driver.
AnnaBridge 156:ff21514d8981 30 *
AnnaBridge 156:ff21514d8981 31 *
AnnaBridge 156:ff21514d8981 32 * @defgroup lib_driver_twi_master Software controlled TWI Master driver
AnnaBridge 156:ff21514d8981 33 * @{
AnnaBridge 156:ff21514d8981 34 * @ingroup nrf_drivers
AnnaBridge 156:ff21514d8981 35 * @brief Software controlled TWI Master driver.
AnnaBridge 156:ff21514d8981 36 *
AnnaBridge 156:ff21514d8981 37 * Supported features:
AnnaBridge 156:ff21514d8981 38 * - Repeated start
AnnaBridge 156:ff21514d8981 39 * - No multi-master
AnnaBridge 156:ff21514d8981 40 * - Only 7-bit addressing
AnnaBridge 156:ff21514d8981 41 * - Supports clock stretching (with optional SMBus style slave timeout)
AnnaBridge 156:ff21514d8981 42 * - Tries to handle slaves stuck in the middle of transfer
AnnaBridge 156:ff21514d8981 43 */
AnnaBridge 156:ff21514d8981 44
AnnaBridge 156:ff21514d8981 45 #define TWI_READ_BIT (0x01) //!< If this bit is set in the address field, transfer direction is from slave to master.
AnnaBridge 156:ff21514d8981 46
AnnaBridge 156:ff21514d8981 47 #define TWI_ISSUE_STOP ((bool)true) //!< Parameter for @ref twi_master_transfer
AnnaBridge 156:ff21514d8981 48 #define TWI_DONT_ISSUE_STOP ((bool)false) //!< Parameter for @ref twi_master_transfer
AnnaBridge 156:ff21514d8981 49
AnnaBridge 156:ff21514d8981 50 /* These macros are needed to see if the slave is stuck and we as master send dummy clock cycles to end its wait */
AnnaBridge 156:ff21514d8981 51 /*lint -e717 -save "Suppress do {} while (0) for these macros" */
AnnaBridge 156:ff21514d8981 52 /*lint ++flb "Enter library region" */
AnnaBridge 156:ff21514d8981 53 #define TWI_SCL_HIGH() do { NRF_GPIO->OUTSET = (1UL << TWI_MASTER_CONFIG_CLOCK_PIN_NUMBER); } while(0) /*!< Pulls SCL line high */
AnnaBridge 156:ff21514d8981 54 #define TWI_SCL_LOW() do { NRF_GPIO->OUTCLR = (1UL << TWI_MASTER_CONFIG_CLOCK_PIN_NUMBER); } while(0) /*!< Pulls SCL line low */
AnnaBridge 156:ff21514d8981 55 #define TWI_SDA_HIGH() do { NRF_GPIO->OUTSET = (1UL << TWI_MASTER_CONFIG_DATA_PIN_NUMBER); } while(0) /*!< Pulls SDA line high */
AnnaBridge 156:ff21514d8981 56 #define TWI_SDA_LOW() do { NRF_GPIO->OUTCLR = (1UL << TWI_MASTER_CONFIG_DATA_PIN_NUMBER); } while(0) /*!< Pulls SDA line low */
AnnaBridge 156:ff21514d8981 57 #define TWI_SDA_INPUT() do { NRF_GPIO->DIRCLR = (1UL << TWI_MASTER_CONFIG_DATA_PIN_NUMBER); } while(0) /*!< Configures SDA pin as input */
AnnaBridge 156:ff21514d8981 58 #define TWI_SDA_OUTPUT() do { NRF_GPIO->DIRSET = (1UL << TWI_MASTER_CONFIG_DATA_PIN_NUMBER); } while(0) /*!< Configures SDA pin as output */
AnnaBridge 156:ff21514d8981 59 #define TWI_SCL_OUTPUT() do { NRF_GPIO->DIRSET = (1UL << TWI_MASTER_CONFIG_CLOCK_PIN_NUMBER); } while(0) /*!< Configures SCL pin as output */
AnnaBridge 156:ff21514d8981 60 /*lint -restore */
AnnaBridge 156:ff21514d8981 61
AnnaBridge 156:ff21514d8981 62 #define TWI_SDA_READ() ((NRF_GPIO->IN >> TWI_MASTER_CONFIG_DATA_PIN_NUMBER) & 0x1UL) /*!< Reads current state of SDA */
AnnaBridge 156:ff21514d8981 63 #define TWI_SCL_READ() ((NRF_GPIO->IN >> TWI_MASTER_CONFIG_CLOCK_PIN_NUMBER) & 0x1UL) /*!< Reads current state of SCL */
AnnaBridge 156:ff21514d8981 64
AnnaBridge 156:ff21514d8981 65 #define TWI_DELAY() nrf_delay_us(4) /*!< Time to wait when pin states are changed. For fast-mode the delay can be zero and for standard-mode 4 us delay is sufficient. */
AnnaBridge 156:ff21514d8981 66
AnnaBridge 156:ff21514d8981 67
AnnaBridge 156:ff21514d8981 68 /**
AnnaBridge 156:ff21514d8981 69 * @brief Function for initializing TWI bus IO pins and checks if the bus is operational.
AnnaBridge 156:ff21514d8981 70 *
AnnaBridge 156:ff21514d8981 71 * Both pins are configured as Standard-0, No-drive-1 (open drain).
AnnaBridge 156:ff21514d8981 72 *
AnnaBridge 156:ff21514d8981 73 * @param twi The TWI interface to use - either NRF_TWI0 or NRF_TWI1
AnnaBridge 156:ff21514d8981 74 * @return
AnnaBridge 156:ff21514d8981 75 * @retval true TWI bus is clear for transfers.
AnnaBridge 156:ff21514d8981 76 * @retval false TWI bus is stuck.
AnnaBridge 156:ff21514d8981 77 */
AnnaBridge 156:ff21514d8981 78 bool twi_master_init_and_clear(NRF_TWI_Type* twi);
AnnaBridge 156:ff21514d8981 79
AnnaBridge 156:ff21514d8981 80 /**
AnnaBridge 156:ff21514d8981 81 * @brief Function for transferring data over TWI bus.
AnnaBridge 156:ff21514d8981 82 *
AnnaBridge 156:ff21514d8981 83 * If TWI master detects even one NACK from the slave or timeout occurs, STOP condition is issued
AnnaBridge 156:ff21514d8981 84 * and the function returns false.
AnnaBridge 156:ff21514d8981 85 * Bit 0 (@ref TWI_READ_BIT) in the address parameter controls transfer direction;
AnnaBridge 156:ff21514d8981 86 * - If 1, master reads data_length number of bytes from the slave
AnnaBridge 156:ff21514d8981 87 * - If 0, master writes data_length number of bytes to the slave.
AnnaBridge 156:ff21514d8981 88 *
AnnaBridge 156:ff21514d8981 89 * @note Make sure at least data_length number of bytes is allocated in data if TWI_READ_BIT is set.
AnnaBridge 156:ff21514d8981 90 * @note @ref TWI_ISSUE_STOP
AnnaBridge 156:ff21514d8981 91 *
AnnaBridge 156:ff21514d8981 92 * @param address Data transfer direction (LSB) / Slave address (7 MSBs).
AnnaBridge 156:ff21514d8981 93 * @param data Pointer to data.
AnnaBridge 156:ff21514d8981 94 * @param data_length Number of bytes to transfer.
AnnaBridge 156:ff21514d8981 95 * @param issue_stop_condition If @ref TWI_ISSUE_STOP, STOP condition is issued before exiting function. If @ref TWI_DONT_ISSUE_STOP, STOP condition is not issued before exiting function. If transfer failed for any reason, STOP condition will be issued in any case.
AnnaBridge 156:ff21514d8981 96 * @param twi The TWI interface to use - either NRF_TWI0 or NRF_TWI1
AnnaBridge 156:ff21514d8981 97 * @return
AnnaBridge 156:ff21514d8981 98 * @retval true Data transfer succeeded without errors.
AnnaBridge 156:ff21514d8981 99 * @retval false Data transfer failed.
AnnaBridge 156:ff21514d8981 100 */
AnnaBridge 156:ff21514d8981 101 bool twi_master_transfer(uint8_t address, uint8_t *data, uint8_t data_length, bool issue_stop_condition, NRF_TWI_Type* twi);
AnnaBridge 156:ff21514d8981 102
AnnaBridge 156:ff21514d8981 103 /**
AnnaBridge 156:ff21514d8981 104 *@}
AnnaBridge 156:ff21514d8981 105 **/
AnnaBridge 156:ff21514d8981 106
AnnaBridge 156:ff21514d8981 107 #ifdef __cplusplus
AnnaBridge 156:ff21514d8981 108 }
AnnaBridge 156:ff21514d8981 109 #endif
AnnaBridge 156:ff21514d8981 110
AnnaBridge 156:ff21514d8981 111 /*lint --flb "Leave library region" */
AnnaBridge 156:ff21514d8981 112 #endif //TWI_MASTER_H