Coding

• replay tester

not done
path includes 02 Coding.md 

Libs

File	Functions	Arguments
robo.h	default_constructor	_servo_id and a Adafruit_PWMServoDriver
robo-movements.h	-	-

• robo.h
• robot-database.h

Program Flow

Here is a quick program functional flow , from the microcontroller perspective

1. Initializes the wifi
2. Initializes the Servo Motors to previous position
3. Check if they are in their initial positions ?
   • Servo motors does not support checking of angle. So im gonna use a server for that.

graph TB
A[Initializes the Wifi] & AA[Initializes the Server Endpoints] --> Main_Thread
B[Retrive Data from the Server] --> C
C[Servo Object] --> Main_Thread 
D[API End Points] --> Main_Thread

• Complete the below 📅 2025-05-24

sequenceDiagram
	 participant PCA9685 
	participant ESP32 
	participant Flask API
	participant SQLite DB
	
	%% ESP32 
	ESP32 -->> ESP32: Initialize -> Boot,WiFi STA ..
	ESP32->>PCA9685: Initialize I2C (i2c_addr)
	%% GET Request
	ESP32->>Flask API: GET /robots?id=$id
	Flask API->>SQLite DB: Query all robots
	SQLite DB-->>Flask API: Return robots data
	Flask API-->>ESP32: JSON response with robots
	
	%% POST Request
	ESP32 ->>Flask API: POST /robots {name, type}
	Flask API->>SQLite DB: Insert new robot
	SQLite DB-->>Flask API: Confirm insertion
	Flask API-->>ESP32: JSON response (201 Created)

There are 3 main Hardware componets that will effect the programming

1. PCA9685 -> For Driving the motor
2. ESP32 -> Main Controller
3. Raspberry Pi -> For hosting the server

PCA9685

#include <Adafruit_PWMServoDriver.h>
Adafruit_PWMServoDriver board1 = Adafruit_PWMServoDriver(0x40);    
#define SERVO_MIN_PULSE_COUNT 125                                              
#define SERVO_MAX_PULSE_COUNT  625                                             
#define SERVO_UPDATE_FREQ
void setup() {
	board1.begin();
	board1.setPWMFreq(SERVO_UPDATE_FREQ);                  
}

void loop() 
  { 
	for(int i=0; i<8; i++){
		board1.setPWM(i, 0, get_pulse(0) );
	}
    delay(1000);
    for( int angle =0; angle<181; angle +=10)
      { 
      for(int i=0; i<8; i++){ board1.setPWM(i, 0, get_pulse(angle) );}
      }
    delay(100);
  }
int get_pulse(int angle)                             
{ 
	int pulse = map(angle,0, 180, SERVO_MIN_PULSE_COUNT,SERVO_MAX_PULSE_COUNT); 
    return pulse;
  }

This is the PCA9685 driver #sampleCode , here is its order

1. Create driver_object
   • param: i2c_addr

Adafruit_PWMServoDriver board1 = Adafruit_PWMServoDriver(0x40); 

// Adafruit_PWMServoDriver.cpp
Adafruit_PWMServoDriver();
Adafruit_PWMServoDriver(const uint8_t addr);
Adafruit_PWMServoDriver(const uint8_t addr, TwoWire &i2c);

There are 3 defenitions

	Adafruit_PWMServoDriver::Adafruit_PWMServoDriver(const uint8_t addr)
	: _i2caddr(addr), _i2c(&Wire) {}
	/*!
	 *  @brief  Instantiates a new PCA9685 PWM driver chip with the I2C address on a
	 * TwoWire interface
	 *  @param  addr The 7-bit I2C address to locate this chip, default is 0x40
	 *  @param  i2c  A reference to a 'TwoWire' object that we'll use to communicate

2. Initialize the board

• Complete these steps 📅 2025-05-24

Servo

There is mainly x things

1. Servo Properties

#define SERVO_ANGLE_MIN 0
#define SERVO_ANGLE_MAX 180
#define SERVO_MIN  102   // .5ms
#define SERVO_MAX  512   // 2.5ms 
#define SERVO_FREQ 50
#define CONTROLLER_I2C_ADDR 0x41

But we have to make sure it our self .

Database

Movements

Software

Going to use platformio for development and cpp as the programming language , vscode as the editor(ide).

Adafruit_PWMServoDriver board1 = Adafruit_PWMServoDriver(CONTROLLER_I2C_ADDR);      

Robo la1(PIN_LA1, board1);
Robo la2(PIN_LA2, board1);
Robo la3(PIN_LA3, board1);
Robo ra1(PIN_RA1, board1);
Robo ra2(PIN_RA2, board1);
Robo ra3(PIN_RA3, board1);
Robo lh(PIN_LH, board1);
Robo rh(PIN_RH, board1);
Robo ll1(PIN_LL1, board1);
Robo ll2(PIN_LL2, board1);
Robo ll3(PIN_LL3, board1);
Robo rl1(PIN_RL1, board1);
Robo rl2(PIN_RL2, board1);
Robo rl3(PIN_RL3, board1);
Robo lf(PIN_LF, board1);
Robo rf(PIN_RF, board1);