AVR Microcontroller Blinking LED Not Working

I am trying to learn embedded electronics using the 8-bit AVR microcontroller and whilst I have experience with electronics and programming I am a noob with embedded systems. The chip I am trying to program is the Atmega168. I am following the Make: AVR Programming book but I am at a complete loss trying to understand why the LED is failing to blink even after following the book.

I have tried troubleshooting both hardware and software side without any success. I am using an arduino as an ISP and the chip has no bootloader. I have tried programming through the Arduino IDE and through VS code terminal. The commands for compilation and uploading complete sucessfully and AVRdude says I have flashed 174bytes.

The circuit I am using to try and program the Atmega168 with arduino as ISP is taken directly from the book I am reading. I have attached a photo to help understand it. There is a red LED which is on and indicating power supply is OK. The green LED is being driven from PBO (Pin 14). I was initially powering the chip from the Arduino 5v power supply but have since in my inexperience and frustration changed to powering from about 3.2 volts from a voltage divider not realising that 5v is within the operating voltage for the chip.

The commands that I am running for compiling the C program and uploading are as follows;

avr-gcc -mmcu=atmega168 -Os blinkLED.c -o blinkLED.elf
objcopy -O ihex blinkLED.elf blinkLED.hex
avrdude -p m168 -c avrisp -P COM4 -b 19200 -U flash:w:blinkLED.hex

After the commands successfully run the LED does nothing. The C program that is being compiled and flashed to the microcontroller is copied directly from the github repo and is as follows;

/* Blinker Demo */

// -------- Macros -------//
#define F_CPU 1000000UL

// ------- Preamble -------- //
#include <avr/io.h>                        /* Defines pins, ports, etc */
#include <util/delay.h>                     /* Functions to waste time */

int main(void) {

    // -------- Inits --------- //
    DDRB |= 0b00000001;            

    // ------ Event loop ------ //
    while (1) {

      PORTB = 0b00000001;          /* Turn on first LED bit/pin in PORTB */
      _delay_ms(1000);                                           /* wait */

      PORTB = 0b00000000;          /* Turn off all B pins, including LED */
      _delay_ms(1000);                                           /* wait */

    }                                                  /* End event loop */
    return 0;                            /* This line is never reached */
}

I have tried different a different mcu when compiling with avr-gcc but this usually results in errors or warnings so I assume atmega168 is correct and not say atmega168P. As stated previous I have tried in mutliple IDE’s and no error warnings when compiling or flashing. All the com port and baud rate settings are good as whenever I change these I can no longer communicate with the microcontrolller through AVRdude. I have checked the wiring multiple times so I assume I have not done anything silly with the wiring and even after compeletely re-wiring according to the book no difference.

I have tried googling and changing code and rewiring and spent hours troubleshooting. Whilst the troubleshooting has helped improve my understanding of the toolchain I can’t actually start anything interesting until I get this working. Given that everything is compiling and uploading OK is making it difficult to understand why it is not working. Any help or advice is very much appreciated.

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