mbed official / mbed-dev

mbed library sources. Supersedes mbed-src.

Dependents:   Nucleo_Hello_Encoder BLE_iBeaconScan AM1805_DEMO DISCO-F429ZI_ExportTemplate1 ... more

targets/TARGET_NORDIC/TARGET_MCU_NRF51822/twi_master.h@189:f392fc9709a3, 2019-02-20 (annotated)

Committer:
AnnaBridge
Date:
Wed Feb 20 22:31:08 2019 +0000
Revision:
189:f392fc9709a3
Parent:
149:156823d33999 
mbed library release version 165

Who changed what in which revision?

UserRevisionLine numberNew contents of line
<> 144:ef7eb2e8f9f7 1 /* Copyright (c) 2009 Nordic Semiconductor. All Rights Reserved.
<> 144:ef7eb2e8f9f7 2 *
<> 144:ef7eb2e8f9f7 3 * The information contained herein is property of Nordic Semiconductor ASA.
<> 144:ef7eb2e8f9f7 4 * Terms and conditions of usage are described in detail in NORDIC
<> 144:ef7eb2e8f9f7 5 * SEMICONDUCTOR STANDARD SOFTWARE LICENSE AGREEMENT.
<> 144:ef7eb2e8f9f7 6 *
<> 144:ef7eb2e8f9f7 7 * Licensees are granted free, non-transferable use of the information. NO
<> 144:ef7eb2e8f9f7 8 * WARRANTY of ANY KIND is provided. This heading must NOT be removed from
<> 144:ef7eb2e8f9f7 9 * the file.
<> 144:ef7eb2e8f9f7 10 *
<> 144:ef7eb2e8f9f7 11 */
<> 144:ef7eb2e8f9f7 12
<> 144:ef7eb2e8f9f7 13 #ifndef TWI_MASTER_H
<> 144:ef7eb2e8f9f7 14 #define TWI_MASTER_H
<> 144:ef7eb2e8f9f7 15
<> 144:ef7eb2e8f9f7 16
<> 144:ef7eb2e8f9f7 17 #ifdef __cplusplus
<> 144:ef7eb2e8f9f7 18 extern "C" {
<> 144:ef7eb2e8f9f7 19 #endif
<> 144:ef7eb2e8f9f7 20
<> 144:ef7eb2e8f9f7 21 /*lint ++flb "Enter library region" */
<> 144:ef7eb2e8f9f7 22
<> 144:ef7eb2e8f9f7 23 #include <stdbool.h>
<> 144:ef7eb2e8f9f7 24 #include <stdint.h>
<> 144:ef7eb2e8f9f7 25
<> 144:ef7eb2e8f9f7 26 #include "nrf51.h"
<> 144:ef7eb2e8f9f7 27
<> 144:ef7eb2e8f9f7 28 /** @file
<> 144:ef7eb2e8f9f7 29 * @brief Software controlled TWI Master driver.
<> 144:ef7eb2e8f9f7 30 *
<> 144:ef7eb2e8f9f7 31 *
<> 144:ef7eb2e8f9f7 32 * @defgroup lib_driver_twi_master Software controlled TWI Master driver
<> 144:ef7eb2e8f9f7 33 * @{
<> 144:ef7eb2e8f9f7 34 * @ingroup nrf_drivers
<> 144:ef7eb2e8f9f7 35 * @brief Software controlled TWI Master driver.
<> 144:ef7eb2e8f9f7 36 *
<> 144:ef7eb2e8f9f7 37 * Supported features:
<> 144:ef7eb2e8f9f7 38 * - Repeated start
<> 144:ef7eb2e8f9f7 39 * - No multi-master
<> 144:ef7eb2e8f9f7 40 * - Only 7-bit addressing
<> 144:ef7eb2e8f9f7 41 * - Supports clock stretching (with optional SMBus style slave timeout)
<> 144:ef7eb2e8f9f7 42 * - Tries to handle slaves stuck in the middle of transfer
<> 144:ef7eb2e8f9f7 43 */
<> 144:ef7eb2e8f9f7 44
<> 144:ef7eb2e8f9f7 45 #define TWI_READ_BIT (0x01) //!< If this bit is set in the address field, transfer direction is from slave to master.
<> 144:ef7eb2e8f9f7 46
<> 144:ef7eb2e8f9f7 47 #define TWI_ISSUE_STOP ((bool)true) //!< Parameter for @ref twi_master_transfer
<> 144:ef7eb2e8f9f7 48 #define TWI_DONT_ISSUE_STOP ((bool)false) //!< Parameter for @ref twi_master_transfer
<> 144:ef7eb2e8f9f7 49
<> 144:ef7eb2e8f9f7 50 /* These macros are needed to see if the slave is stuck and we as master send dummy clock cycles to end its wait */
<> 144:ef7eb2e8f9f7 51 /*lint -e717 -save "Suppress do {} while (0) for these macros" */
<> 144:ef7eb2e8f9f7 52 /*lint ++flb "Enter library region" */
<> 144:ef7eb2e8f9f7 53 #define TWI_SCL_HIGH() do { NRF_GPIO->OUTSET = (1UL << TWI_MASTER_CONFIG_CLOCK_PIN_NUMBER); } while(0) /*!< Pulls SCL line high */
<> 144:ef7eb2e8f9f7 54 #define TWI_SCL_LOW() do { NRF_GPIO->OUTCLR = (1UL << TWI_MASTER_CONFIG_CLOCK_PIN_NUMBER); } while(0) /*!< Pulls SCL line low */
<> 144:ef7eb2e8f9f7 55 #define TWI_SDA_HIGH() do { NRF_GPIO->OUTSET = (1UL << TWI_MASTER_CONFIG_DATA_PIN_NUMBER); } while(0) /*!< Pulls SDA line high */
<> 144:ef7eb2e8f9f7 56 #define TWI_SDA_LOW() do { NRF_GPIO->OUTCLR = (1UL << TWI_MASTER_CONFIG_DATA_PIN_NUMBER); } while(0) /*!< Pulls SDA line low */
<> 144:ef7eb2e8f9f7 57 #define TWI_SDA_INPUT() do { NRF_GPIO->DIRCLR = (1UL << TWI_MASTER_CONFIG_DATA_PIN_NUMBER); } while(0) /*!< Configures SDA pin as input */
<> 144:ef7eb2e8f9f7 58 #define TWI_SDA_OUTPUT() do { NRF_GPIO->DIRSET = (1UL << TWI_MASTER_CONFIG_DATA_PIN_NUMBER); } while(0) /*!< Configures SDA pin as output */
<> 144:ef7eb2e8f9f7 59 #define TWI_SCL_OUTPUT() do { NRF_GPIO->DIRSET = (1UL << TWI_MASTER_CONFIG_CLOCK_PIN_NUMBER); } while(0) /*!< Configures SCL pin as output */
<> 144:ef7eb2e8f9f7 60 /*lint -restore */
<> 144:ef7eb2e8f9f7 61
<> 144:ef7eb2e8f9f7 62 #define TWI_SDA_READ() ((NRF_GPIO->IN >> TWI_MASTER_CONFIG_DATA_PIN_NUMBER) & 0x1UL) /*!< Reads current state of SDA */
<> 144:ef7eb2e8f9f7 63 #define TWI_SCL_READ() ((NRF_GPIO->IN >> TWI_MASTER_CONFIG_CLOCK_PIN_NUMBER) & 0x1UL) /*!< Reads current state of SCL */
<> 144:ef7eb2e8f9f7 64
<> 144:ef7eb2e8f9f7 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. */
<> 144:ef7eb2e8f9f7 66
<> 144:ef7eb2e8f9f7 67
<> 144:ef7eb2e8f9f7 68 /**
<> 144:ef7eb2e8f9f7 69 * @brief Function for initializing TWI bus IO pins and checks if the bus is operational.
<> 144:ef7eb2e8f9f7 70 *
<> 144:ef7eb2e8f9f7 71 * Both pins are configured as Standard-0, No-drive-1 (open drain).
<> 144:ef7eb2e8f9f7 72 *
<> 144:ef7eb2e8f9f7 73 * @param twi The TWI interface to use - either NRF_TWI0 or NRF_TWI1
<> 144:ef7eb2e8f9f7 74 * @return
<> 144:ef7eb2e8f9f7 75 * @retval true TWI bus is clear for transfers.
<> 144:ef7eb2e8f9f7 76 * @retval false TWI bus is stuck.
<> 144:ef7eb2e8f9f7 77 */
<> 144:ef7eb2e8f9f7 78 bool twi_master_init_and_clear(NRF_TWI_Type* twi);
<> 144:ef7eb2e8f9f7 79
<> 144:ef7eb2e8f9f7 80 /**
<> 144:ef7eb2e8f9f7 81 * @brief Function for transferring data over TWI bus.
<> 144:ef7eb2e8f9f7 82 *
<> 144:ef7eb2e8f9f7 83 * If TWI master detects even one NACK from the slave or timeout occurs, STOP condition is issued
<> 144:ef7eb2e8f9f7 84 * and the function returns false.
<> 144:ef7eb2e8f9f7 85 * Bit 0 (@ref TWI_READ_BIT) in the address parameter controls transfer direction;
<> 144:ef7eb2e8f9f7 86 * - If 1, master reads data_length number of bytes from the slave
<> 144:ef7eb2e8f9f7 87 * - If 0, master writes data_length number of bytes to the slave.
<> 144:ef7eb2e8f9f7 88 *
<> 144:ef7eb2e8f9f7 89 * @note Make sure at least data_length number of bytes is allocated in data if TWI_READ_BIT is set.
<> 144:ef7eb2e8f9f7 90 * @note @ref TWI_ISSUE_STOP
<> 144:ef7eb2e8f9f7 91 *
<> 144:ef7eb2e8f9f7 92 * @param address Data transfer direction (LSB) / Slave address (7 MSBs).
<> 144:ef7eb2e8f9f7 93 * @param data Pointer to data.
<> 144:ef7eb2e8f9f7 94 * @param data_length Number of bytes to transfer.
<> 144:ef7eb2e8f9f7 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.
<> 144:ef7eb2e8f9f7 96 * @param twi The TWI interface to use - either NRF_TWI0 or NRF_TWI1
<> 144:ef7eb2e8f9f7 97 * @return
<> 144:ef7eb2e8f9f7 98 * @retval true Data transfer succeeded without errors.
<> 144:ef7eb2e8f9f7 99 * @retval false Data transfer failed.
<> 144:ef7eb2e8f9f7 100 */
<> 144:ef7eb2e8f9f7 101 bool twi_master_transfer(uint8_t address, uint8_t *data, uint8_t data_length, bool issue_stop_condition, NRF_TWI_Type* twi);
<> 144:ef7eb2e8f9f7 102
<> 144:ef7eb2e8f9f7 103 /**
<> 144:ef7eb2e8f9f7 104 *@}
<> 144:ef7eb2e8f9f7 105 **/
<> 144:ef7eb2e8f9f7 106
<> 144:ef7eb2e8f9f7 107 #ifdef __cplusplus
<> 144:ef7eb2e8f9f7 108 }
<> 144:ef7eb2e8f9f7 109 #endif
<> 144:ef7eb2e8f9f7 110
<> 144:ef7eb2e8f9f7 111 /*lint --flb "Leave library region" */
<> 144:ef7eb2e8f9f7 112 #endif //TWI_MASTER_H