Diff: LT_I2C.cpp

Revision:

0:6be57f391716

Child:

1:6d4265aa4184

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/LT_I2C.cpp	Wed Aug 23 10:49:21 2017 +0000
@@ -0,0 +1,252 @@
+#include "LT_I2C.h"
+
+/* mbed headers */
+#include <mbed.h>
+#include <I2C.h>
+
+extern "C" {
+
+static I2C *i2c_object = NULL;
+
+int lt_i2c_init(int sda, int scl) {
+    if (i2c_object == NULL) {
+        i2c_object = new I2C((PinName) sda, (PinName) scl);
+        return LT_I2C_INIT_FINE;
+    }
+    else {
+        return LT_I2C_INIT_QUIT_FIRST;
+    }
+}
+
+int lt_i2c_quit() {
+    delete i2c_object;
+    return LT_I2C_SUCCESS;
+}
+
+int lt_i2c_init_attach(void *p_i2c_object) {
+    if (i2c_object == NULL) {
+        i2c_object = (I2C *) p_i2c_object;
+        return LT_I2C_INIT_FINE;
+    }
+    else {
+        return LT_I2C_INIT_QUIT_FIRST;
+    }
+}
+
+void *lt_i2c_get_i2c_object() {
+    return i2c_object;
+}
+
+#define CHECK_OBJECT    if (i2c_object == NULL) return LT_I2C_FAILURE;
+
+int lt_i2c_start() {
+    CHECK_OBJECT
+    i2c_object->start();
+    return LT_I2C_SUCCESS;
+}
+
+int lt_i2c_stop() {
+    CHECK_OBJECT
+    i2c_object->stop();
+    return LT_I2C_SUCCESS;
+}
+
+uint8_t lt_i2c_write(uint8_t data) {
+    CHECK_OBJECT
+    return 1-i2c_object->write(data); // I wish casting will work fine
+    // must return 0 if ACK was received (1- is due that)
+}
+
+uint8_t lt_i2c_read(int8_t ack) {
+    CHECK_OBJECT
+    return (uint8_t) (i2c_object->read(1-ack)); // act is different in mbed
+}
+
+int8_t lt_i2c_write_byte_data(
+    uint8_t address,
+    uint8_t command,
+    uint8_t value) {
+    CHECK_OBJECT
+    int8_t ret = 0;
+    if (lt_i2c_start()!=0) //I2C START
+        return(1);      //Stop and return 0 if START fail
+    ret |= lt_i2c_write((address<<1)|LT_I2C_WRITE_BIT);
+        // Write 7 bit address with W bit
+    ret|= lt_i2c_write(command);   // Set register to be read to command
+    ret|= lt_i2c_write(value);
+    lt_i2c_stop(); // I2C STOP
+    if (ret!=0)     //If there was a NAK return 1
+        return(1);
+    return(0);      // Return success
+}
+
+int8_t lt_i2c_write_word_data(
+    uint8_t address,
+    uint8_t command,
+    uint16_t value) {
+    CHECK_OBJECT
+    int8_t ret=0;
+    union
+    {
+        uint8_t b[2];
+        uint16_t w;
+    } data;
+    data.w = value;
+    if (lt_i2c_start()!=0) //I2C START
+        return(1);      //Stop and return 0 if START fail
+    ret |= lt_i2c_write((address<<1)|LT_I2C_WRITE_BIT);
+        // Write 7 bit address with W bit
+    ret|= lt_i2c_write(command);   // Set register to be read to command
+    ret|= lt_i2c_write(data.b[1]); //Write MSB
+    ret|= lt_i2c_write(data.b[0]); //Write LSB;
+    lt_i2c_stop(); // I2C STOP
+    if (ret!=0) //If there was a NAK return 1
+        return(1);
+    return(0);
+}
+
+uint8_t lt_i2c_write_block_data(
+    uint8_t address,
+    uint8_t command,
+    uint8_t length,
+    uint8_t *values) {
+    CHECK_OBJECT
+    int8_t i = length-1;
+    int8_t ret = 0;
+    if (lt_i2c_start()!=0) //I2C START
+        return(1);      //Stop and return 0 if START fail
+    ret |= lt_i2c_write((address<<1)|LT_I2C_WRITE_BIT);
+        // Write 7 bit address with W bit
+    ret|= lt_i2c_write(command);   // Set register to be read to command
+    while (i>=0)
+    {
+        ret|= lt_i2c_write(values[i]); //Write Value
+        i--;
+    }
+    lt_i2c_stop(); // I2C STOP
+    if (ret!=0)
+        return(1);
+    else
+        return(0);  // Success!
+}
+
+uint8_t lt_i2c_read_byte_data(
+    uint8_t address,
+    uint8_t command,
+    uint8_t *value) {
+    CHECK_OBJECT
+    int8_t ret = 0;
+    if (lt_i2c_start() != 0) // I2C START
+    {
+        return (1); // Stop and return 0 if START fail
+    }
+    ret |= lt_i2c_write((address << 1) | LT_I2C_WRITE_BIT); // Write 7 bit address with W bit
+    if (ret != 0) // If NACK return 1
+    {
+        lt_i2c_stop(); // I2C STOP
+        return (1);
+    }
+    ret |= lt_i2c_write(command); // Set register to be read to command
+    if (ret != 0) // If NACK return 1
+    {
+        lt_i2c_stop(); // I2C STOP
+        return (1);
+    }
+    if (lt_i2c_start() != 0) // I2C repeated START
+    {
+        lt_i2c_stop(); // Attempt to issue I2C STOP
+        return (1); // Stop and return 0 if START fail
+    }
+    ret |= lt_i2c_write((address << 1) | LT_I2C_READ_BIT); // Write 7 bit address with R bit
+    *value = lt_i2c_read(LT_I2C_WITH_NACK); // Read byte from buffer with NAK
+    lt_i2c_stop(); // I2C STOP
+    if (ret != 0) // If there was a NACK return 1
+    {
+        return (1);
+    }
+    return (0); // Return success
+}
+
+uint8_t lt_i2c_read_word_data(
+    uint8_t address,
+    uint8_t command,
+    uint16_t *value) {
+    CHECK_OBJECT
+    int8_t ret = 0;
+    union {
+        uint8_t b[2];
+        uint16_t w;
+    } data;
+    if (lt_i2c_start() != 0) //I2C START
+        return (1); //Stop and return 0 if START fail
+    ret |= lt_i2c_write((address << 1) | LT_I2C_WRITE_BIT); // Write 7 bit address with W bit
+    if (ret != 0) //If NACK return 1
+    {
+        lt_i2c_stop(); //I2C STOP
+        return (1);
+    }
+    ret |= lt_i2c_write(command); // Set register to be read to command
+    if (ret != 0) //If NACK return 1
+    {
+        lt_i2c_stop(); //I2C STOP
+        return (1);
+    }
+    if (lt_i2c_start() != 0) //I2C START
+    {
+        lt_i2c_stop(); //Attempt to issue I2C STOP
+        return (1); //Stop and return 0 if START fail
+    }
+    ret |= lt_i2c_write((address << 1) | LT_I2C_READ_BIT); // Write 7 bit address with R bit
+    data.b[1] = lt_i2c_read(LT_I2C_WITH_ACK); // Read MSB from buffer
+    data.b[0] = lt_i2c_read(LT_I2C_WITH_NACK); // Read LSB from buffer
+    lt_i2c_stop(); //I2C STOP
+    *value = data.w;
+    if (ret != 0) //If NAK
+        return (1); //return 1
+    return (0); // Return success
+}
+
+uint8_t lt_i2c_read_block_data(
+    uint8_t address,
+    uint8_t command,
+    uint8_t length,
+    uint8_t *values) {
+    CHECK_OBJECT
+    uint8_t i = (length - 1);
+    int8_t ret = 0;
+    if (lt_i2c_start() != 0) //I2C START
+        return (1); //Stop and return 0 if START fail
+    ret |= lt_i2c_write((address << 1) | LT_I2C_WRITE_BIT); //Write 7-bit address with W bit
+    if (ret != 0) //If NACK return 1
+    {
+        lt_i2c_stop(); //I2C STOP
+        return (1);
+    }
+    ret |= lt_i2c_write(command); //Write 8 bit command word
+    if (ret != 0) //If NACK return 1
+    {
+        lt_i2c_stop(); //I2C STOP
+        return (1);
+    }
+    if (lt_i2c_start() != 0) //I2C repeated START
+    {
+        lt_i2c_stop(); //Attempt to issue I2C STOP
+        return (1); //Stop and return 0 if START fail
+    }
+    ret |= lt_i2c_write((address << 1) | LT_I2C_READ_BIT); //Write 7-bit address with R bit
+    if (ret != 0) //If NACK return 1
+    {
+        lt_i2c_stop(); //I2C STOP
+        return (1);
+    }
+    while (i > 0) //Begin read loop
+    {
+        values[i] = lt_i2c_read(LT_I2C_WITH_ACK); //Read from bus with ACK
+        i--;
+    }
+    values[0] = lt_i2c_read(LT_I2C_WITH_NACK); //Read from bus with NACK for the last one;
+    lt_i2c_stop(); //I2C STOP    
+    return (0); // Success!
+}
+
+}