Atmega32 blink incorrect. Problem with oscillator

1

Hi, I’m new to platformio. I’m writing code for ATmega32 and using usbasp to upload code. I have a MCU on my board without external clock generator. I wrote a simple code to blink led on PB1. But for some reason instead of 1 second period, 8 seconds pass. I changed clock to 1 MHz and blink period became 1 second. Do I need 16 MHz crystal or do I need to change something in config file?

[env:ATmega32]
platform = atmelavr
board = ATmega32
framework = arduino
upload_protocol = usbasp
board_build.f_cpu = 8000000L

#include <Arduino.h>
#define led PB1
// put function declarations here:

void setup() {
  // put your setup code here, to run once:
pinMode(led, OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
  digitalWrite(led, 1); delay(1000);
  digitalWrite(led, 0); delay(1000);
}
2

The default fuse values of an ATMega32 set it up for 1MHz internal clock. So if you tell PlatformIO that you have

But you only actually have 1 MHz, then everything will run 8 times slower. Which is exactly what you observe.

Calculate the right fuse settings and burn them into your device:

grafik
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