high_speed_logger_direct_memory.c

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/*
 * Copyright (C) 2014 Clement Roblot
 *
 * This file is part of paparazzi.
 *
 * paparazzi is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * paparazzi is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with paparazzi; see the file COPYING.  If not, see
 * <http://www.gnu.org/licenses/>.
 */
 
#include "high_speed_logger_direct_memory.h"
 
#include <string.h>
 
#include "modules/imu/imu.h"
#include "mcu_periph/spi.h"
#include "mcu_periph/uart.h"
 
#include "modules/datalink/downlink.h"
#include "modules/datalink/telemetry.h"
 
 
/******************************************************************/
/*                                                                */
/*                  Config values, go crazy                       */
/*                                                                */
/******************************************************************/
#define READING_BLOCK_SIZE 200
#define ERASE_MEMORY_AT_START 0
#define SIZE_OF_LOGGED_VALUES 4
#define SIZE_OF_VALUES_NAMES 10
 
#define SKIP_X_CALLS_BETWEEN_VALUES 0
 
#define NBR_VALUES_TO_LOG 9
 
uint32_t values_to_log[NBR_VALUES_TO_LOG] = {
 
  //That list must be pointers to the variables
  //you want to log
 
  (uint32_t) &imu.accel_unscaled.x,
  (uint32_t) &imu.accel_unscaled.y,
  (uint32_t) &imu.accel_unscaled.z,
 
  (uint32_t) &imu.gyro_unscaled.p,
  (uint32_t) &imu.gyro_unscaled.q,
  (uint32_t) &imu.gyro_unscaled.r,
 
  (uint32_t) &imu.mag_unscaled.x,
  (uint32_t) &imu.mag_unscaled.y,
  (uint32_t) &imu.mag_unscaled.z
};
 
 
 
char **name_of_the_values = (char * [SIZE_OF_VALUES_NAMES])
{
  "acc x",
  "acc y",
  "acc z",
  "gyro p",
  "gyro q",
  "gyro r",
  "mag x",
  "mag y",
  "mag z"
};
 
 
 
/******************************************************************/
/*                                                                */
/*                  Fixed values, do not touch                    */
/*                                                                */
/******************************************************************/
#define MEMORY_READ_LATTENCY 5
#define TOTAL_MEMORY_SIZE 32
#define END_OF_MEMORY_THRESHOLD 10
 
 
//log start-start_of_values-end flags
uint8_t start_log_sequence[6] = {0xAA, 0x55, 0xFF, 0x00, 0x55, 0xAA};
uint8_t start_values_sequence[3] = {0xF0, 0xF0, 0xA5};
uint8_t start_lost_values_sequence[6] = {0x42, 0x0F, 0X42, 0X00, 0XFF, 0xAA};
uint8_t stop_lost_values_sequence[6] = {0xAA, 0xFF, 0x00, 0x42, 0x0F, 0x42};
 
 
uint8_t stop_log_sequence[6] = {0xFF, 0x00, 0x55, 0xAA, 0x00, 0xFF};
 
//low level buffers used to communicate over SPI
uint8_t buff[25];   //25 is enough even for the reading of the ID (24 values)
uint8_t uart_read_buff[READING_BLOCK_SIZE + MEMORY_READ_LATTENCY] = {0};
uint8_t msg[10];
uint8_t values_send_buffer[256];
 
//local buffer used to log values
uint8_t buffer_values_logged[256];
uint8_t nbr_values_in_buffer = 0;
uint8_t buffer_values_sending[256];
uint8_t nbr_values_in_buffer_sending = 0;
uint8_t buffer_used = 0;
 
//local status flags
uint8_t wait_answear_from_reading_memory = 0;
uint8_t memory_status_byte;
uint8_t sending_buffer_to_uart = 0;
uint8_t relaunch_reading_memory = 0;
uint8_t continue_reading_memory = 0;
 
 
//memory management variables
uint32_t current_writting_addr = 0x00000000;
uint32_t current_unerased_addr = 0x00000000;
uint32_t current_reading_addr = 0x00000000;
static volatile bool memory_ready = true;
struct spi_transaction memory_transaction;
struct spi_transaction memory_send_value_transaction;
uint32_t nbr_lost_values = 0;
 
 
uint8_t logging_status_gui;
 
 
 
static void memory_transaction_done_cb(struct spi_transaction *trans);
static void memory_read_status_cb(struct spi_transaction *trans);
static void memory_read_values_cb(struct spi_transaction *trans);
 
 
/******************************************************************/
/*                                                                */
/*      Low level function, directly acting with the SPI          */
/*                                                                */
/******************************************************************/
 
void memory_read_id(void)
{
 
  memory_ready = false;
  msg[0] = 0x9F;
 
  memory_transaction.output_buf    = (uint8_t *) msg;
  memory_transaction.output_length = 1;
 
  memory_transaction.input_buf = (uint8_t *) buff;
  memory_transaction.input_length = 24;
 
  memory_transaction.after_cb = memory_transaction_done_cb;
 
  spi_submit(&(HIGH_SPEED_LOGGER_DIRECT_MEMORY_DEVICE), &memory_transaction);
}
 
void memory_send_wren(void)
{
  memory_ready = false;
  msg[0] = 0x06;
 
  memory_transaction.output_buf    = (uint8_t *) msg;
  memory_transaction.output_length = 1;
 
  memory_transaction.input_buf = NULL;
  memory_transaction.input_length = 0;
 
  memory_transaction.after_cb = memory_transaction_done_cb;
 
  spi_submit(&(HIGH_SPEED_LOGGER_DIRECT_MEMORY_DEVICE), &memory_transaction);
}
 
void memory_send_wrdi(void)
{
  memory_ready = false;
  msg[0] = 0x04;
 
  memory_transaction.output_buf    = (uint8_t *) msg;
  memory_transaction.output_length = 1;
 
  memory_transaction.input_buf = NULL;
  memory_transaction.input_length = 0;
 
  memory_transaction.after_cb = memory_transaction_done_cb;
 
  spi_submit(&(HIGH_SPEED_LOGGER_DIRECT_MEMORY_DEVICE), &memory_transaction);
}
 
void memory_read_status_1(void)
{
  memory_ready = false;
  msg[0] = 0x05;
 
  memory_transaction.output_buf    = (uint8_t *) msg;
  memory_transaction.output_length = 1;
 
  memory_transaction.input_buf = (uint8_t *) buff;
  memory_transaction.input_length = 4;
 
  memory_transaction.after_cb = memory_read_status_cb;
 
  spi_submit(&(HIGH_SPEED_LOGGER_DIRECT_MEMORY_DEVICE), &memory_transaction);
}
 
static void memory_read_status_cb(struct spi_transaction *trans __attribute__((unused)))
{
 
  memory_ready = true;
 
  memory_status_byte = buff[1];
  wait_answear_from_reading_memory = 0;
}
 
void memory_erase_4k(uint32_t mem_addr)
{
 
  uint8_t *addr = (uint8_t *) &mem_addr;
 
  memory_ready = false;
  msg[0] = 0x21;
  msg[1] = addr[3];
  msg[2] = addr[2];
  msg[3] = addr[1];
  msg[4] = addr[0];
 
  memory_transaction.output_buf    = (uint8_t *) msg;
  memory_transaction.output_length = 5;
 
  memory_transaction.input_buf = NULL;
  memory_transaction.input_length = 0;
 
  memory_transaction.after_cb = memory_transaction_done_cb;
 
  spi_submit(&(HIGH_SPEED_LOGGER_DIRECT_MEMORY_DEVICE), &memory_transaction);
}
 
void memory_completly_erase(void)
{
 
  memory_ready = false;
  msg[0] = 0xC7;
 
  memory_transaction.output_buf    = (uint8_t *) msg;
  memory_transaction.output_length = 1;
 
  memory_transaction.input_buf = NULL;
  memory_transaction.input_length = 0;
 
  memory_transaction.after_cb = memory_transaction_done_cb;
 
  spi_submit(&(HIGH_SPEED_LOGGER_DIRECT_MEMORY_DEVICE), &memory_transaction);
}
 
void memory_write_values(uint32_t mem_addr, uint8_t *values, uint8_t size)
{
 
  uint8_t *addr = (uint8_t *) &mem_addr;
  uint8_t i;
 
  memory_ready = false;
  values_send_buffer[0] = 0x12;
  values_send_buffer[1] = addr[3];
  values_send_buffer[2] = addr[2];
  values_send_buffer[3] = addr[1];
  values_send_buffer[4] = addr[0];
 
  for (i = 0; i < size; i++) {
    values_send_buffer[i + 5] = values[i];
  }
 
  memory_send_value_transaction.output_buf    = (uint8_t *) values_send_buffer;
  memory_send_value_transaction.output_length = 5 + size;
 
  memory_send_value_transaction.input_buf = NULL;
  memory_send_value_transaction.input_length = 0;
 
  memory_send_value_transaction.after_cb = memory_transaction_done_cb;
 
  spi_submit(&(HIGH_SPEED_LOGGER_DIRECT_MEMORY_DEVICE), &memory_send_value_transaction);
}
 
void memory_read_values(uint32_t mem_addr, uint8_t size)
{
 
  uint8_t *addr = (uint8_t *) &mem_addr;
 
  memory_ready = false;
  msg[0] = 0x13;
  msg[1] = addr[3];
  msg[2] = addr[2];
  msg[3] = addr[1];
  msg[4] = addr[0];
 
  memory_transaction.output_buf    = (uint8_t *) msg;
  memory_transaction.output_length = 5;
 
  memory_transaction.input_buf = (uint8_t *) uart_read_buff;
  memory_transaction.input_length = size +
                                    MEMORY_READ_LATTENCY; //the first MEMORY_READ_LATTENCY Bytes are lost because of reading to soon
 
  memory_transaction.after_cb = memory_read_values_cb;
 
  spi_submit(&(HIGH_SPEED_LOGGER_DIRECT_MEMORY_DEVICE), &memory_transaction);
}
 
static void memory_read_values_cb(struct spi_transaction *trans __attribute__((unused)))
{
 
  uint8_t msg_size = memory_transaction.input_length;
 
  memory_ready = true;
 
  if (msg_size) {
 
    if (is_sequence_in_array(uart_read_buff, msg_size, stop_log_sequence, 6)) { //this is the end of the log
 
      current_reading_addr = 0;
      relaunch_reading_memory = 0;
 
    } else { //this is not the end of the log
 
      relaunch_reading_memory = 1;
    }
 
    sending_buffer_to_uart = 1;
    send_buffer_to_uart();
  }
}
 
static void memory_transaction_done_cb(struct spi_transaction *trans __attribute__((unused)))
{
  memory_ready = true;
}
 
 
 
 
/******************************************************************/
/*                                                                */
/*     Mid low level functions, abstracting the low SPI layer     */
/*                                                                */
/******************************************************************/
 
uint8_t ml_write_values_to_memory(uint32_t mem_addr, uint8_t *values, uint8_t size)
{
  static uint8_t ml_write_values_to_memory_status = 0;
  static uint32_t previus_mem_addr = 0;
  static uint8_t *previus_values = NULL;
  static uint8_t previus_size = 0;
 
 
  //test if we are stating a new writting cicle
  if ((ml_write_values_to_memory_status == 0) &&
      ((previus_mem_addr != mem_addr) || (previus_values != values) || (previus_size != size))) {
 
    ml_write_values_to_memory_status = 1;
    previus_mem_addr = mem_addr;
    previus_values = values;
    previus_size = size;
  }
 
  switch (ml_write_values_to_memory_status) {
 
    case 0 :
      //waiting for something to do
      break;
 
    case 1 :
      memory_send_wren();
      ml_write_values_to_memory_status = 2;
      //break;
      //we imediatly send the values after this message.
      //The low level functions are not using the same buffers
      //so we can do it
 
    case 2 :
      memory_write_values(mem_addr, values, size);
      ml_write_values_to_memory_status = 3;
      wait_answear_from_reading_memory = 1;
      break;
 
    case 3 :
      memory_read_status_1();  //we wait for the writting to be done
      if ((wait_answear_from_reading_memory) || (memory_status_byte)) {
        ml_write_values_to_memory_status = 3;
      } else { //the writting has been completed
        ml_write_values_to_memory_status = 0;
      }
      break;
 
    default :
      break;
  }
 
  return ml_write_values_to_memory_status;
}
 
 
uint8_t ml_erase_4k_on_memory(uint32_t mem_addr)
{
 
  static uint8_t ml_erase_4k_on_memory_status = 0;
 
  switch (ml_erase_4k_on_memory_status) {
 
    case 0 :
      memory_send_wren();
      ml_erase_4k_on_memory_status = 1;
      break;
 
    case 1 :
      memory_erase_4k(mem_addr);
      ml_erase_4k_on_memory_status = 2;
      wait_answear_from_reading_memory = 1;
      break;
 
    case 2 :
      memory_read_status_1();  //we wait for the writting to be done
      if ((wait_answear_from_reading_memory) || (memory_status_byte)) {
        ml_erase_4k_on_memory_status = 2;
      } else { //the erasing have been completed
        ml_erase_4k_on_memory_status = 0;
      }
      break;
 
    default :
      break;
  }
 
  return ml_erase_4k_on_memory_status;
}
 
 
uint8_t ml_erase_completely_memory(void)
{
 
  static uint8_t ml_erase_memory_status = 0;
 
  switch (ml_erase_memory_status) {
 
    case 0 :
      memory_send_wren();
      ml_erase_memory_status = 1;
      break;
 
    case 1 :
      memory_completly_erase();
      ml_erase_memory_status = 2;
      wait_answear_from_reading_memory = 1;
      break;
 
    case 2 :
      memory_read_status_1();  //we wait for the writting to be done
      if ((wait_answear_from_reading_memory) || (memory_status_byte)) {
        ml_erase_memory_status = 2;
      } else { //the erasing have been completed
        ml_erase_memory_status = 0;
      }
      break;
 
    default : break;
  }
 
  return ml_erase_memory_status;
}
 
 
void ml_read_log_in_memory(void)
{
  memory_read_values(current_reading_addr, READING_BLOCK_SIZE);
  current_reading_addr += READING_BLOCK_SIZE;
}
 
 
 
 
 
/******************************************************************/
/*                                                                */
/*      Mid high level function : memory management               */
/*                                                                */
/******************************************************************/
 
uint8_t append_values_to_memory(uint8_t *values, uint8_t size)
{
 
  static uint8_t append_to_memory_status = 0;
  static uint8_t index_value_unwritten = 0;
  uint8_t return_code = 1;
  uint8_t size_data_left_to_write;
  uint8_t wait_for_SPI = 0;
 
  uint32_t size_used_in_current_page, size_left_current_page, size_to_write;
 
  while (!wait_for_SPI) {
 
    switch (append_to_memory_status) {
 
      case 0 :
        if (!ERASE_MEMORY_AT_START) {
          if ((current_unerased_addr - current_writting_addr) > size) { //we got enough cleared space to write the value
 
            append_to_memory_status = 1;
          } else {
 
            if (!ml_erase_4k_on_memory(current_unerased_addr)) {
 
              current_unerased_addr += 4096;   //65536
            } else {
 
              wait_for_SPI = 1;
            }
          }
        } else {
 
          append_to_memory_status = 1;
        }
        break;
 
 
      case 1 :
        //we start writting the values
        //need to fit the values in pages of 4K
 
        //256 bytes per pages
        size_used_in_current_page = (current_writting_addr & 0x000000FF);
        size_left_current_page = 0x00000100 - size_used_in_current_page;
 
        size_data_left_to_write = size - index_value_unwritten;
        if (size_left_current_page > size_data_left_to_write) { size_to_write = size_data_left_to_write; }
        else { size_to_write = size_left_current_page; }
 
        if (size_to_write > 250) { size_to_write = 250; } //protection against overflows in the lower levels
 
        if (size_to_write > 0) {
 
          if (!ml_write_values_to_memory(current_writting_addr, &values[index_value_unwritten], size_to_write)) {
 
            index_value_unwritten += size_to_write;
            current_writting_addr += size_to_write;
 
            if (index_value_unwritten == size) {
 
              append_to_memory_status = 0;
              index_value_unwritten = 0;
              return_code = 0;
            }
 
            //test is we are close to the end of the memory
            if (((TOTAL_MEMORY_SIZE << 20) - current_writting_addr) < (END_OF_MEMORY_THRESHOLD << 10)) {
              //if we got less than END_OF_MEMORY_THRESHOLD kilo Bytes of mem left
 
              logging_status_gui = 3; //we stop the logging
            }
 
 
          }
 
          wait_for_SPI = 1;
        }
        break;
 
      default:
        break;
    }
  }
 
  return return_code;
}
 
 
 
void send_buffer_to_uart(void)
{
 
  uint8_t msg_size = memory_transaction.input_length;
  static uint8_t i = MEMORY_READ_LATTENCY;
  long fd = 0;
 
  if (sending_buffer_to_uart) {
 
    while (uart_check_free_space(&HS_LOG_UART, &fd, 1)) {
 
      if (i >= msg_size) {
 
        sending_buffer_to_uart = 0;
        i = MEMORY_READ_LATTENCY;
        if (relaunch_reading_memory && continue_reading_memory) {
 
          continue_reading_memory = 0;
          ml_read_log_in_memory();
        }
        break;
      }
      uart_put_byte(&HS_LOG_UART, fd, uart_read_buff[i]);
      i++;
    }
 
  } else {
 
    i = MEMORY_READ_LATTENCY;
    if (relaunch_reading_memory && continue_reading_memory) {
      continue_reading_memory = 0;
      ml_read_log_in_memory();
    }
  }
}
 
 
 
uint8_t send_buffer_to_memory(uint8_t *buffer, uint8_t *size)
{
 
  uint8_t return_code = 1;
 
  if (*size > 0) {
    if (!append_values_to_memory(buffer, *size)) {
      *size = 0;
      return_code = 0;
    }
  } else {
    return_code = 0;
  }
 
  return return_code;
}
 
 
 
 
/******************************************************************/
/*                                                                */
/*      High level function : local buffer management             */
/*                                                                */
/******************************************************************/
 
void add_byte_to_buffer(uint8_t value)
{
  if (buffer_used) {
 
    if (nbr_values_in_buffer_sending < 0xFF) {
      buffer_values_sending[nbr_values_in_buffer_sending] = value;
      nbr_values_in_buffer_sending++;
    } else {
      nbr_lost_values++;
    }
 
  } else {
 
    if (nbr_values_in_buffer < 0xFF) {
      buffer_values_logged[nbr_values_in_buffer] = value;
      nbr_values_in_buffer++;
    } else {
      nbr_lost_values++;
    }
  }
}
 
void add_array_to_buffer(uint8_t *array, uint8_t size)
{
  uint8_t i;
 
  for (i = 0; i < size; i++) {
    add_byte_to_buffer(array[i]);
  }
}
 
uint8_t run_memory_management(void)
{
  uint8_t return_code = 1;
  uint8_t *log_value_tmp;
 
  if (buffer_used) {
 
    if (!send_buffer_to_memory(buffer_values_logged, &nbr_values_in_buffer)) {
 
      buffer_used = 0;
 
      if (nbr_lost_values) {
 
        add_array_to_buffer(start_lost_values_sequence, 6);
 
        log_value_tmp = (uint8_t *) &nbr_lost_values;
        add_byte_to_buffer(log_value_tmp[0]);
        add_byte_to_buffer(log_value_tmp[1]);
        add_byte_to_buffer(log_value_tmp[2]);
        add_byte_to_buffer(log_value_tmp[3]);
 
        add_array_to_buffer(stop_lost_values_sequence, 6);
        nbr_lost_values = 0;
      }
 
      return_code = 0;
    }
  } else {
 
    if (!send_buffer_to_memory(buffer_values_sending, &nbr_values_in_buffer_sending)) {
 
      buffer_used = 1;
 
      if (nbr_lost_values) {
 
        add_array_to_buffer(start_lost_values_sequence, 6);
 
        log_value_tmp = (uint8_t *) &nbr_lost_values;
        add_byte_to_buffer(log_value_tmp[0]);
        add_byte_to_buffer(log_value_tmp[1]);
        add_byte_to_buffer(log_value_tmp[2]);
        add_byte_to_buffer(log_value_tmp[3]);
 
        add_array_to_buffer(stop_lost_values_sequence, 6);
        nbr_lost_values = 0;
      }
 
      return_code = 0;
    }
  }
 
  return return_code;
}
 
 
 
uint8_t are_buffers_empty(void)
{
  uint8_t return_value = 0;
 
  if ((nbr_values_in_buffer == 0) && (nbr_values_in_buffer_sending == 0)) {
    return_value = 1;
  }
 
  return return_value;
}
 
 
 
 
/******************************************************************/
/*                                                                */
/*      High level function : log management                    */
/*                                                                */
/******************************************************************/
 
uint8_t start_new_log(void)
{
 
  static uint8_t start_log_status = 0;
  uint8_t return_code = 1;
 
  char msg_names[(SIZE_OF_VALUES_NAMES + 1)*NBR_VALUES_TO_LOG] = "";
  uint8_t i;
 
  for (i = 0; i < NBR_VALUES_TO_LOG; i++) {
 
    strcat(msg_names, name_of_the_values[i]);
    if (i != (NBR_VALUES_TO_LOG - 1)) { strcat(msg_names, ";"); } //we don't put a ';' at the end of the list
  }
 
  switch (start_log_status) {
 
    case 0 :
      current_writting_addr = 0x00000000; //restart the writting at the begining of the memory
      current_unerased_addr = 0x00000000;
 
      if (ERASE_MEMORY_AT_START) {
 
        if (!ml_erase_completely_memory()) {
 
          start_log_status = 1;
        }
      } else {
 
        start_log_status = 1;
      }
      break;
 
 
    case 1 :
      add_array_to_buffer(start_log_sequence, 6);
      add_byte_to_buffer(SIZE_OF_LOGGED_VALUES);
      start_log_status = 2;
      break;
 
    case 2 :
      add_array_to_buffer((uint8_t *)msg_names, (SIZE_OF_VALUES_NAMES + 1)*NBR_VALUES_TO_LOG);
      start_log_status = 3;
      break;
 
    case 3 :
      add_array_to_buffer(start_values_sequence, 3);
      start_log_status = 0;
      return_code = 0;
      break;
 
    default :
      break;
  }
 
  return return_code;
}
 
 
void add_values_to_buffer(void)
{
  uint8_t *log_value_tmp;
  uint8_t i, j;
 
  for (i = 0; i < NBR_VALUES_TO_LOG; i++) {
 
    log_value_tmp = (uint8_t *) values_to_log[i];
 
    for (j = 0; j < SIZE_OF_LOGGED_VALUES; j++) {
 
      add_byte_to_buffer(log_value_tmp[j]);
    }
  }
}
 
 
void run_logger(void)
{
  static uint8_t i = 0;
  //useless variable. It simply remove a warning when SKIP_X_CALLS_BETWEEN_VALUES=0 and the test is always true
  uint8_t limit = SKIP_X_CALLS_BETWEEN_VALUES;
 
  if (i >= limit) {  //3 with erase memory, 0 WITHOUT SKIP_X_CALLS_BETWEEN_VALUES
    add_values_to_buffer();
    i = 0;
  }
  i++;
}
 
 
uint8_t end_log(void)
{
  uint8_t return_value = 1;
 
  if (are_buffers_empty()) { //if the buffers are empty to prevent from writting during a buffer overflow
    add_array_to_buffer(stop_log_sequence, 6);
    return_value = 0;
  }
 
  return return_value;
}
 
 
 
 
/******************************************************************/
/*                                                                */
/*                      Module function                           */
/*                                                                */
/******************************************************************/
 
 
void high_speed_logger_direct_memory_init(void)
{
  //init the SPI to communicat with the memory
  memory_transaction.select        = SPISelectUnselect;
  memory_transaction.cpol          = SPICpolIdleHigh;
  memory_transaction.cpha          = SPICphaEdge2;
  memory_transaction.dss           = SPIDss8bit;
  memory_transaction.bitorder      = SPIMSBFirst;
  memory_transaction.cdiv          = SPIDiv64;
  memory_transaction.slave_idx     = HIGH_SPEED_LOGGER_DIRECT_MEMORY_SLAVE_NUMBER;
  memory_transaction.select        = SPISelectUnselect;
  memory_transaction.output_buf    = NULL;
  memory_transaction.output_length = 0;
  memory_transaction.input_buf     = NULL;
  memory_transaction.input_length  = 0;
  memory_transaction.after_cb      = memory_transaction_done_cb;
 
  spi_submit(&(HIGH_SPEED_LOGGER_DIRECT_MEMORY_DEVICE), &memory_transaction);
 
 
  memory_send_value_transaction.select        = SPISelectUnselect;
  memory_send_value_transaction.cpol          = SPICpolIdleHigh;
  memory_send_value_transaction.cpha          = SPICphaEdge2;
  memory_send_value_transaction.dss           = SPIDss8bit;
  memory_send_value_transaction.bitorder      = SPIMSBFirst;
  memory_send_value_transaction.cdiv          = SPIDiv64;
  memory_send_value_transaction.slave_idx     = HIGH_SPEED_LOGGER_DIRECT_MEMORY_SLAVE_NUMBER;
  memory_send_value_transaction.select        = SPISelectUnselect;
  memory_send_value_transaction.output_buf    = NULL;
  memory_send_value_transaction.output_length = 0;
  memory_send_value_transaction.input_buf     = NULL;
  memory_send_value_transaction.input_length  = 0;
  memory_send_value_transaction.after_cb      = memory_transaction_done_cb;
 
 
 
  //init the UART to send the values back to the computer
  uart_periph_init(&HS_LOG_UART);
  uart_periph_set_bits_stop_parity(&HS_LOG_UART, 8, 1, 0);
}
 
 
 
void high_speed_logger_direct_memory_periodic(void)
{
  uint8_t uart_received;
 
  //UART part (communication with the computer to dump the memory)
  while (uart_char_available(&HS_LOG_UART)) {
 
    uart_received = uart_getch(&HS_LOG_UART);
 
    if (uart_received == 'A') {
      continue_reading_memory = 1;
      ml_read_log_in_memory();
 
    } else if (uart_received == 'B') {
      continue_reading_memory = 1;
    }
  }
 
 
  //SPI part (to log the values on the memory when in flight)
  if (memory_ready) {
 
    switch (logging_status_gui) {
 
      case 0 :
        //idle state, nothing to do
        break;
 
      case 1 :
        //start a new log
        if (!start_new_log()) { logging_status_gui = 0; }
        break;
 
      case 2 :
        //logging values
        run_logger();
        break;
 
      case 3 :
        //finishing the log
        if (!end_log()) { logging_status_gui = 0; }
        break;
 
      default :
        break;
    }
 
    run_memory_management();
  }
 
  //this function regulats itself, we have to call it at every iteration of the module
  send_buffer_to_uart();
}
 
 
 
/******************************************************************/
/*                                                                */
/*                      Other functions                           */
/*                                                                */
/******************************************************************/
 
uint8_t is_sequence_in_array(uint8_t *array, uint8_t array_size, uint8_t *sequence, uint8_t sequence_size)
{
  uint8_t i = MEMORY_READ_LATTENCY;
  static uint8_t current_sequence_id = 0;
 
  for (i = MEMORY_READ_LATTENCY; i < array_size; i++) {
 
    if (array[i] == sequence[current_sequence_id]) {
      current_sequence_id++;
      if (current_sequence_id >= sequence_size) {
        current_sequence_id = 0;
        return 1;
      }
    } else {
      current_sequence_id = 0;
    }
  }
 
  return 0;
}
 
 
void high_speed_logger_direct_memory_handler(uint8_t val)
{
  logging_status_gui = val;
}