main.cpp File Reference

This contains the main driver code for the flight computer. More...

#include <Arduino.h>
#include <Wire.h>
#include <WiFi.h>
#include <PubSubClient.h>
#include <TinyGPSPlus.h>
#include <SFE_BMP180.h>
#include <FS.h>
#include <SD.h>
#include <SPIFFS.h>
#include "defs.h"
#include "mpu.h"
#include "SerialFlash.h"
#include "logger.h"
#include "data_types.h"
#include "custom_time.h"
#include "states.h"
#include "system_logger.h"
#include "system_log_levels.h"
#include "wifi-config.h"

Macros
#define	BAUDRATE   115200
#define	NAK_INTERVAL   4000
#define	SOH   0x01
#define	EOT   0x04
#define	ACK   0x06
#define	NAK   0x15
#define	CAN   0x18
#define	MAX_CMD_LENGTH   10
#define	MAX_CSV_LENGTH   256
#define	FORMAT_SPIFFS_IF_FAILED   1
#define	TRANSMIT_TELEMETRY_BIT   ((EventBits_t) 0x01 << 0)
#define	CHECK_FLIGHT_STATE_BIT   ((EventBits_t) 0x01 << 1)
#define	LOG_TO_MEMORY_BIT   ((EventBits_t) 0x01 << 2)
#define	TRANSMIT_XBEE_BIT   ((EventBits_t) 0x01 << 3)
#define	DEBUG_TO_TERM_BIT   ((EventBits_t) 0x01 << 4)
#define	ALTITUDE   1525.0

Enumerations
enum	TEST_STATE { HANDSHAKE = 0 , RECEIVE_TEST_DATA , CONFIRM_TEST_DATA }
	This enum holds the states during flight computer test mode. More...

Functions
void	drogueChuteDeploy ()
	fires the pyro-charge to deploy the drogue chute Turn on the drogue chute ejection circuit by running the GPIO HIGH for a preset No. of seconds. Default no. of seconds to remain HIGH is 5
void	mainChuteDeploy ()
	fires the pyro-charge to deploy the main chute Turn on the main chute ejection circuit by running the GPIO HIGH for a preset No. of seconds. Default no. of seconds to remain HIGH is 5
void	listDir (fs::FS &fs, const char *dirname, uint8_t levels)
void	initGPIO ()
	Inititialize the GPIOs.
void	InitSPIFFS ()
void	initSD ()
void	SwitchLEDs (uint8_t red_state, uint8_t green_state)
	Switch the LEDS states.
void	InitXMODEM ()
	Initiate XMODEM protocol by sending a NAK command every 4 seconds until the transmitter returns an ACK signal.
void	SerialEvent ()
void	ParseSerial (char *)
void	checkRunTestToggle ()
	Sample the RUN/TEST toggle pins to check whether the fligh tcomputer is in test mode or run mode. If in TEST mode, define the TEST flag If in RUN mode, define the RUN flag TEST_MODE Pin and RUN_MODE pin are both pulled HIGH. When you set the jumper, you pull that pin to LOW.
void	readFile (fs::FS &fs, const char *path)
void	writeFile (fs::FS &fs, const char *path, const char *message)
void	appendFile (fs::FS &fs, const char *path, const char *message)
void	deleteFile (fs::FS &fs, const char *path)
void	readTestDataFile ()
void	buzz ()
	Buzz the buzzer for a given buzz_interval This function is non-blocking.
void	blink_200ms (uint8_t led_pin)
	implements non-blocking blink
void	ParseSerialBuffer (char *buffer)
void	ParseSerialNumeric (int value)
	Parse the received serial command if it is a digit We are only interested in numeric values being sent by the transmitter to us, the receiver.
void	handshakeSerialEvent ()
	Receive serial message during handshake.
void	receiveTestDataSerialEvent ()
	Receive serial message during RECEIVE_TEST_DATA state Data received in this state is the actual test data. It is saved into the test flash memory.
void	BMPInit ()
	Initialize BMP180 barometric sensor.
void	GPSInit ()
	Initialize the GPS connected on Serial2.
void	readAccelerationTask (void *pvParameter)
	Read acceleration data from the accelerometer.
void	readAltimeterTask (void *pvParameters)
	Read ar pressure data from the barometric sensor onboard.
void	readGPSTask (void *pvParameters)
	Read the GPS location data and altitude and append to telemetry packet for transmission.
void	clearTelemetryQueueTask (void *pvParameters)
	dequeue data from telemetry queue after all the tasks have consumed the data
void	checkFlightState (void *pvParameters)
	Check and update the current state of flight - refer to states.h.
void	flightStateCallback (void *pvParameters)
	performs flight actions based on the current flight state If the flight state neccessisates an operation, we perform it here For example if the flight state is apogee, we perform MAIN_CHUTE ejection
void	debugToTerminalTask (void *pvParameters)
	debug flight/test data to terminal, this task is called if the DEBUG_TO_TERMINAL is set to 1 (see defs.h)
void	logToMemory (void *pvParameter)
	log the data to the external flash memory
void	MQTT_TransmitTelemetry (void *pvParameters)
	send flight data to ground
void	MQTT_Reconnect ()
	Try reconnecting to MQTT if connection is lost.
void	MQTTInit (const char *broker_IP, int broker_port)
	Initialize MQTT.
void	setup ()
	Setup - perform initialization of all hardware subsystems, create queues, create queue handles initialize system check table.
void	loop ()
	Main loop.

Variables
uint8_t	operation_mode = 0
uint8_t	current_state = FLIGHT_STATE::PRE_FLIGHT_GROUND
TinyGPSPlus	gps
SystemLogger	system_logger
const char *	system_log_file = "/sys_log.log"
LOG_LEVEL	level = INFO
const char *	rocket_ID = "rocket-1"
uint8_t	RUN_MODE = 0
uint8_t	TEST_MODE = 0
uint8_t	SOH_recvd_flag = 0
unsigned long	last_NAK_time = 0
unsigned long	current_NAK_time = 0
char	SOH_CHR [6] = "SOH"
char	serial_buffer [MAX_CMD_LENGTH]
int16_t	serial_index = 0
char	test_data_buffer [MAX_CSV_LENGTH]
int16_t	test_data_serial_index = 0
uint8_t	recv_data_led = 2
uint8_t	red_led = 15
uint8_t	green_led = 4
uint8_t	buzzer = 33
uint8_t	SET_TEST_MODE_PIN = 14
uint8_t	SET_RUN_MODE_PIN = 13
uint8_t	SD_CS_PIN = 26
uint8_t	current_test_state = TEST_STATE::HANDSHAKE
const char *	test_data_file = "/data.csv"
unsigned long	last_buzz = 0
unsigned long	current_buzz = 0
unsigned long	buzz_interval = 200
uint8_t	buzzer_state = LOW
unsigned long	last_blink = 0
unsigned long	current_blink = 0
unsigned long	blink_interval = 200
uint8_t	led_state = LOW
int	value = 0
	Parse the received serial command if it is a string.
WIFIConfig	wifi_config
uint8_t	drogue_pyro = 25
uint8_t	main_pyro = 12
uint8_t	flash_cs_pin = 5
uint8_t	remote_switch = 27
uint8_t	flash_led_pin = 32
char	filename [] = "flight.bin"
uint32_t	FILE_SIZE_512K = 524288L
uint32_t	FILE_SIZE_1M = 1048576L
uint32_t	FILE_SIZE_4M = 4194304L
SerialFlashFile	file
unsigned long long	previous_log_time = 0
unsigned long long	current_log_time = 0
uint16_t	log_sample_interval = 10
DataLogger	data_logger (flash_cs_pin, flash_led_pin, filename, file, FILE_SIZE_4M)
long long	current_time = 0
long long	previous_time = 0
EventGroupHandle_t	tasksDataReceiveEventGroup
accel_type_t	acc_data
gyro_type_t	gyro_data
gps_type_t	gps_data
altimeter_type_t	altimeter_data
telemetry_type_t	telemetry_packet
MPU6050	imu (0x68, 16, 1000)
SFE_BMP180	altimeter
char	status
double	T
double	P
double	p0
double	a
QueueHandle_t	telemetry_data_qHandle
QueueHandle_t	accel_data_qHandle
QueueHandle_t	altimeter_data_qHandle
QueueHandle_t	gps_data_qHandle

Detailed Description

This contains the main driver code for the flight computer.

Author

Edwin Mwiti

Version

0.1

Date

July 15 2024

0x5765206D6179206D616B65206F757220706C616E73202C 0x62757420476F642068617320746865206C61737420776F7264

Macro Definition Documentation

ACK

#define ACK   0x06

positive acknowledgement

CAN

#define CAN   0x18

cancel

EOT

#define EOT   0x04

end of transmission

MAX_CMD_LENGTH

#define MAX_CMD_LENGTH   10

Maximum length of the XMODEM command string that can be received

MAX_CSV_LENGTH

#define MAX_CSV_LENGTH   256

Maximum length of the csv string that can be received

NAK

#define NAK   0x15

negative acknowledgement

NAK_INTERVAL

#define NAK_INTERVAL   4000

Interval in which to send the NAK command to the transmitter

SOH

#define SOH   0x01

start of header

TRANSMIT_TELEMETRY_BIT

#define TRANSMIT_TELEMETRY_BIT   ((EventBits_t) 0x01 << 0)

Task synchronization variables

Enumeration Type Documentation

TEST_STATE

enum TEST_STATE

This enum holds the states during flight computer test mode.

---

Enumerator
HANDSHAKE	state to establish initial communication with transmitter
RECEIVE_TEST_DATA	sets the flight computer to receive test data over serial

Function Documentation

blink_200ms()

void blink_200ms

(

uint8_t

led_pin

)

implements non-blocking blink

---

BMPInit()

void BMPInit

(

)

Initialize BMP180 barometric sensor.

---

Returns

TODO: 1 if init OK, 0 otherwise

buzz()

void buzz

(

)

Buzz the buzzer for a given buzz_interval This function is non-blocking.

---

checkFlightState()

void checkFlightState

(

void *

pvParameters

)

Check and update the current state of flight - refer to states.h.

---

Parameters

pvParameters

- A value that is passed as the parameter to the created task. If pvParameters is set to the address of a variable then the variable must still exist when the created task executes - so it is not valid to pass the address of a stack variable.

Returns

Updates the telemetry data flight state value

checkRunTestToggle()

void checkRunTestToggle

(

)

Sample the RUN/TEST toggle pins to check whether the fligh tcomputer is in test mode or run mode. If in TEST mode, define the TEST flag If in RUN mode, define the RUN flag TEST_MODE Pin and RUN_MODE pin are both pulled HIGH. When you set the jumper, you pull that pin to LOW.

---

clearTelemetryQueueTask()

void clearTelemetryQueueTask

(

void *

pvParameters

)

dequeue data from telemetry queue after all the tasks have consumed the data

---

Parameters

pvParameters

- A value that is passed as the parameter to the created task. If pvParameters is set to the address of a variable then the variable must still exist when the created task executes - so it is not valid to pass the address of a stack variable.

Returns

none

debugToTerminalTask()

void debugToTerminalTask

(

void *

pvParameters

)

debug flight/test data to terminal, this task is called if the DEBUG_TO_TERMINAL is set to 1 (see defs.h)

---

Parameters

pvParameter

- A value that is passed as the parameter to the created task. If pvParameter is set to the address of a variable then the variable must still exist when the created task executes - so it is not valid to pass the address of a stack variable.

drogueChuteDeploy()

void drogueChuteDeploy

(

)

fires the pyro-charge to deploy the drogue chute Turn on the drogue chute ejection circuit by running the GPIO HIGH for a preset No. of seconds.
Default no. of seconds to remain HIGH is 5

---

flightStateCallback()

void flightStateCallback

(

void *

pvParameters

)

performs flight actions based on the current flight state If the flight state neccessisates an operation, we perform it here For example if the flight state is apogee, we perform MAIN_CHUTE ejection

---

Parameters

pvParameter

- A value that is passed as the parameter to the created task. If pvParameter is set to the address of a variable then the variable must still exist when the created task executes - so it is not valid to pass the address of a stack variable.

GPSInit()

void GPSInit

(

)

Initialize the GPS connected on Serial2.

---

Returns

1 if init OK, 0 otherwise

handshakeSerialEvent()

void handshakeSerialEvent

(

)

Receive serial message during handshake.

---

initGPIO()

void initGPIO

(

)

Inititialize the GPIOs.

---

InitXMODEM()

void InitXMODEM

(

)

Initiate XMODEM protocol by sending a NAK command every 4 seconds until the transmitter returns an ACK signal.

XMODEM serial function definition

---

Parameters

none

listDir()

void listDir	(	fs::FS &	fs,
		const char *	dirname,
		uint8_t	levels )

XMODEM serial function prototypes

logToMemory()

void logToMemory

(

void *

pvParameter

)

log the data to the external flash memory

---

Parameters

pvParameter

- A value that is passed as the paramater to the created task. If pvParameter is set to the address of a variable then the variable must still exist when the created task executes - so it is not valid to pass the address of a stack variable.

loop()

void loop

(

)

Main loop.

---

mainChuteDeploy()

void mainChuteDeploy

(

)

fires the pyro-charge to deploy the main chute Turn on the main chute ejection circuit by running the GPIO HIGH for a preset No. of seconds.
Default no. of seconds to remain HIGH is 5

---

MQTT_TransmitTelemetry()

void MQTT_TransmitTelemetry

(

void *

pvParameters

)

send flight data to ground

---

Parameters

pvParameter

- A value that is passed as the paramater to the created task. If pvParameter is set to the address of a variable then the variable must still exist when the created task executes - so it is not valid to pass the address of a stack variable.

MQTTInit()

void MQTTInit	(	const char *	broker_IP,
		int	broker_port )

Initialize MQTT.

---

ParseSerialNumeric()

void ParseSerialNumeric

(

int

value

)

Parse the received serial command if it is a digit We are only interested in numeric values being sent by the transmitter to us, the receiver.

---

readAccelerationTask()

void readAccelerationTask

(

void *

pvParameter

)

Read acceleration data from the accelerometer.

---

Parameters

pvParameters

- A value that is passed as the paramater to the created task. If pvParameters is set to the address of a variable then the variable must still exist when the created task executes - so it is not valid to pass the address of a stack variable.

Returns

Updates accelerometer data struct on the telemetry queue

readAltimeterTask()

void readAltimeterTask

(

void *

pvParameters

)

Read ar pressure data from the barometric sensor onboard.

---

Parameters

pvParameters

- A value that is passed as the parameter to the created task. If pvParameters is set to the address of a variable then the variable must still exist when the created task executes - so it is not valid to pass the address of a stack variable.

Returns

Sends altimeter data to altimeter queue

readGPSTask()

void readGPSTask

(

void *

pvParameters

)

Read the GPS location data and altitude and append to telemetry packet for transmission.

---

Parameters

pvParameters

- A value that is passed as the paramater to the created task. If pvParameters is set to the address of a variable then the variable must still exist when the created task executes - so it is not valid to pass the address of a stack variable.

receiveTestDataSerialEvent()

void receiveTestDataSerialEvent

(

)

Receive serial message during RECEIVE_TEST_DATA state Data received in this state is the actual test data. It is saved into the test flash memory.

---

setup()

void setup

(

)

Setup - perform initialization of all hardware subsystems, create queues, create queue handles initialize system check table.

---

SwitchLEDs()

void SwitchLEDs	(	uint8_t	red_state,
		uint8_t	green_state )

Switch the LEDS states.

---

Variable Documentation

acc_data

accel_type_t acc_data

///////////////////////// DATA TYPES /////////////////////////

current_log_time

unsigned long long current_log_time = 0

What is the processor time right now?

current_state

uint8_t current_state = FLIGHT_STATE::PRE_FLIGHT_GROUND

The starting state - we start at PRE_FLIGHT_GROUND state

current_test_state

uint8_t current_test_state = TEST_STATE::HANDSHAKE

Define current state the flight computer is in

file

SerialFlashFile file

object representing file object for flash memory

FILE_SIZE_1M

uint32_t FILE_SIZE_1M = 1048576L

1MB

FILE_SIZE_4M

uint32_t FILE_SIZE_4M = 4194304L

4MB

FILE_SIZE_512K

uint32_t FILE_SIZE_512K = 524288L

512KB

filename

char filename[] = "flight.bin"

data log filename - Filename must be less than 20 chars, including the file extension

flash_cs_pin

uint8_t flash_cs_pin = 5

External flash memory chip select pin

flash_led_pin

uint8_t flash_led_pin = 32

LED pin connected to indicate flash memory formatting

green_led

uint8_t green_led = 4

Green LED pin

imu

MPU6050 imu(0x68, 16, 1000)	(	0x68	,
		16	,
		1000	)

///////////////////////// END OF DATA VARIABLES ///////////////////////// create an MPU6050 object 0x68 is the address of the MPU set gyro to max deg to 1000 deg/sec set accel fs reading to 16g

log_sample_interval

uint16_t log_sample_interval = 10

After how long should we sample and log data to flash memory?

operation_mode

uint8_t operation_mode = 0

Tells whether software is in safe or flight mode - FLIGHT_MODE=1, SAFE_MODE=0

previous_log_time

unsigned long long previous_log_time = 0

The last time we logged data to memory

recv_data_led

uint8_t recv_data_led = 2

External flash memory chip select pin

red_led

uint8_t red_led = 15

Red LED pin

rocket_ID

const char* rocket_ID = "rocket-1"

Unique ID of the rocket. Change to the needed rocket name before uploading

SD_CS_PIN

uint8_t SD_CS_PIN = 26

Chip select pin for SD card

SET_RUN_MODE_PIN

uint8_t SET_RUN_MODE_PIN = 13

Pin to set the flight computer to RUN mode

SET_TEST_MODE_PIN

uint8_t SET_TEST_MODE_PIN = 14

Pin to set the flight computer to TEST mode

SOH_recvd_flag

uint8_t SOH_recvd_flag = 0

Transmitter acknowledged?

telemetry_data_qHandle

QueueHandle_t telemetry_data_qHandle

///////////////////////// END OF PERIPHERALS INIT /////////////////////////

value

int value = 0

Parse the received serial command if it is a string.

---

wifi_config

WIFIConfig wifi_config

MQTT helper instances, if using MQTT to transmit telemetry