add preliminary fan control application (wip)

#

# Automatically generated file; DO NOT EDIT.

# Configuration

#

#

# System

#

CONFIG_loop=y

# CONFIG_wakeup is not set

# CONFIG_aspectc is not set

CONFIG_i2c_freq=100000

CONFIG_framebuffer=y

# CONFIG_framebuffer_in_text_segment is not set

CONFIG_framebuffer_width=128

CONFIG_framebuffer_height=32

#

# Libraries

#

# CONFIG_lib_inflate is not set

# CONFIG_arch_arduino_nano is not set

CONFIG_arch_arduino_uno=y

# CONFIG_arch_atmega2560 is not set

# CONFIG_arch_blinkenrocket is not set

# CONFIG_arch_infineon_tc299_mock is not set

# CONFIG_arch_infineon_tc397_mock is not set

# CONFIG_arch_lm4f120h5qr_stellaris is not set

# CONFIG_arch_lora32u4ii is not set

# CONFIG_arch_msp430fr5969lp is not set

# CONFIG_arch_msp430fr5994lp is not set

# CONFIG_arch_posix is not set

# CONFIG_arch_rm46l8lp is not set

# CONFIG_arch_stm32f103c8t6 is not set

# CONFIG_arch_stm32f446re_nucleo is not set

# CONFIG_arch_stm32f746zg_nucleo is not set

# CONFIG_arch_stm32h747i_disco is not set

# CONFIG_arch_tc1796_triboard is not set

CONFIG_arch="arduino-uno"

#

# Arduino Uno Configuration

#

CONFIG_arch_arduino_uno_cpufreq=16000000

CONFIG_arch_arduino_uno_driver_adc=y

CONFIG_arch_arduino_uno_driver_i2c=y

# CONFIG_arch_arduino_uno_driver_neopixel is not set

# CONFIG_arch_arduino_uno_driver_spi is not set

# CONFIG_arch_arduino_uno_driver_stdin is not set

# CONFIG_arch_arduino_uno_driver_timer is not set

# CONFIG_arch_arduino_uno_driver_dmx is not set

# CONFIG_app_datalogger is not set

CONFIG_app_forced_convection=y

# CONFIG_app_ledblink is not set

# CONFIG_app_lora32u4ii is not set

# CONFIG_app_sdtest is not set

# CONFIG_app_ssd1306_128x32_bad_apple is not set

# CONFIG_app_ssd1306test is not set

CONFIG_app="forced-convection"

CONFIG_meta_driver_adc=y

CONFIG_meta_driver_hardware_i2c=y

CONFIG_meta_driver_i2c=y

#

# Drivers

#

# CONFIG_driver_ads111x is not set

# CONFIG_driver_am2320 is not set

# CONFIG_driver_bme280 is not set

# CONFIG_driver_bme680 is not set

# CONFIG_driver_ccs811 is not set

# CONFIG_driver_ds2482 is not set

# CONFIG_driver_eeprom24lc64 is not set

# CONFIG_driver_hdc1080 is not set

CONFIG_driver_lm75=y

# CONFIG_driver_max44006 is not set

# CONFIG_driver_max44009 is not set

# CONFIG_driver_mmsimple is not set

# CONFIG_driver_mmsubstate is not set

# CONFIG_driver_mpu9250 is not set

# CONFIG_driver_s5851a is not set

# CONFIG_driver_scd4x is not set

# CONFIG_driver_sen5x is not set

# CONFIG_driver_sen66 is not set

# CONFIG_driver_veml6075 is not set

CONFIG_driver_ssd1306=y

CONFIG_driver_ssd1306_width=128

CONFIG_driver_ssd1306_height=32

CONFIG_driver_ssd1306_mode_vertical=y

# CONFIG_driver_ssd1306_mode_horizontal is not set

CONFIG_driver_ssd1306_i2c_name="softi2c"

# CONFIG_driver_tsl2591 is not set

CONFIG_driver_softi2c=y

#

# SoftI2C Configuration

#

CONFIG_driver_softi2c_scl="a1"

CONFIG_driver_softi2c_sda="a0"

# CONFIG_driver_softi2c_pullup_none is not set

CONFIG_driver_softi2c_pullup_dynamic_internal=y

# Copyright 2026 Birte Kristina Friesel

#

# SPDX-License-Identifier: CC0-1.0

prompt "Forced Convection"

depends on loop && !wakeup

# vim:ft=make

#

# Copyright 2026 Birte Kristina Friesel

#

# SPDX-License-Identifier: CC0-1.0

ifdef app

	loop = 1

endif

/*

 * Copyright 2026 Birte Kristina Friesel

 *

 * SPDX-License-Identifier: BSD-2-Clause

 */

#include "arch.h"

#include "driver/adc.h"

#include "driver/gpio.h"

#include "driver/stdout.h"

#include "driver/i2c.h"

#include "driver/soft_i2c.h"

#include "driver/lm75.h"

#include "driver/ssd1306.h"

#include "lib/pixelfont/pixeloperator_mirrored.h"

#include "object/framebuffer.h"

#define shift_ser GPIO::d8

#define shift_clk GPIO::d4

#define shift_latch GPIO::d12

#define shift_en GPIO::d7

#define PWM1 OCR2A

#define PWM2 OCR2B

#define PWM3 OCR0A

#define PWM4 OCR0B

#define PWM1_EN _BV(5)

#define PWM2_EN _BV(3)

#define PWM3_EN _BV(0)

#define PWM4_EN _BV(7)

unsigned char graph[88];

unsigned char graph_offset = 0;

void loop(void)

{

	static int seconds = 0;

	static int fan_speed = 0;

	gpio.led_on(0);

	float temp = lm75.getTemp();

	if (temp < 25) {

		PWM1 = 0;

		PWM2 = 0;

		PWM3 = 0;

		PWM4 = 0;

		TCCR0A = 0;

		TCCR2A = 0;

		TCCR0B = 0;

		TCCR2B = 0;

		fan_speed = 0;

	}

	else if (temp >= 30) {

		PWM1 = 255;

		PWM2 = 255;

		PWM3 = 255;

		PWM4 = 255;

		TCCR0A = _BV(COM0A1) | _BV(COM0B1) | _BV(WGM01) | _BV(WGM00);

		TCCR2A = _BV(COM2A1) | _BV(COM2B1) | _BV(WGM21) | _BV(WGM20);

		TCCR0B = _BV(CS00);

		TCCR2B = _BV(CS20);

		fan_speed = 100;

	}

	if (seconds++ == 60) {

		if (temp < 20) {

			graph[graph_offset ] = 0;

		}

		else if (temp > 40) {

			graph[graph_offset ] = 31;

		}

		else {

			graph[graph_offset] = (temp - 20) * 1.5;

		}

		seconds = 0;

		graph_offset = (graph_offset + 1) % (sizeof(graph) / sizeof(graph[0]));

	}

	uint16_t vcc = adc.getVCC_mV() - 200;

	fb.clear();

	fb.setFont(pixeloperator_mirrored);

	fb.setPos(88, 0);

	fb << temp << "c";

	fb.setPos(88, 16);

	fb << vcc/1000 << "." << (vcc%1000)/100 << (vcc%100)/10 << "V";

	fb.setPos(88, 24);

	fb << fan_speed << "%";

	for (unsigned char i = 0; i < (sizeof(graph) / sizeof(graph[0])); i++) {

		unsigned char column_value = graph[(graph_offset + i) % (sizeof(graph) / sizeof(graph[0]))];

		fb.data[i*4 + 3 - (column_value/8)] = 1 << ( 7 - column_value%8);

	}

	ssd1306.showImage(fb.data, fb.width * fb.height / 8);

	kout << "temperature_celsius: ";

	kout.printf_float(temp);

	kout << endl;

	gpio.led_off(0);

}

int main(void)

{

	arch.setup();

	gpio.setup();

	kout.setup();

	gpio.led_on(0);

	/*

	 * Ensure that the SSD1306 OLED display gets a clean reset / power cycle

	 */

	gpio.output(GPIO::a2, 0);

	gpio.output(GPIO::a3, 0);

	arch.delay_ms(50);

	gpio.write(GPIO::a2, 1);

	gpio.write(GPIO::a3, 0);

	arch.delay_ms(50);

	if (i2c.setup() != 0) {

		kout << "I2C setup FAILED" << endl;

		return 1;

	}

	kout << "I2C setup OK" << endl;

	if (softi2c.setup() != 0) {

		kout << "SoftI2C setup FAILED" << endl;

		return 1;

	}

	kout << "SoftI2C setup OK" << endl;

	lm75.setOS(30);

	lm75.setHyst(25);

	ssd1306.init();

	fb.setFont(pixeloperator_mirrored);

	gpio.output(shift_ser, 0);

	gpio.output(shift_clk, 0);

	gpio.output(shift_latch, 0);

	gpio.output(shift_en, 0);

	gpio.output(GPIO::pd3, 0); // OC2B - D3

	gpio.output(GPIO::pd5, 0); // OC0B - D5

	gpio.output(GPIO::pd6, 0); // OC0A - D6

	gpio.output(GPIO::pb3, 0); // OC2A - D11

	// m4a m2a m1a m1b m2b m3a m4b m3b

	uint8_t shift_out = 0b10101001;

	for (unsigned int i = 0; i < 8; i++) {

		gpio.write(shift_ser, shift_out & (1<<i));

		gpio.write(shift_clk, 1);

		gpio.write(shift_clk, 0);

	}

	gpio.write(shift_latch, 1);

	gpio.write(shift_latch, 0);

	gpio.led_off(0);

	arch.idle_loop();

	return 0;

}