https://github.com/styczynski/avr-weather-esp8266
Weather fetching through wifi with LCD1602 + Atmega32 + ESP8266
https://github.com/styczynski/avr-weather-esp8266
arduino atmega avr esp01 esp8266 iot lcd1602 wifi
Last synced: 5 months ago
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Weather fetching through wifi with LCD1602 + Atmega32 + ESP8266
- Host: GitHub
- URL: https://github.com/styczynski/avr-weather-esp8266
- Owner: styczynski
- License: mit
- Created: 2017-06-20T00:04:21.000Z (over 8 years ago)
- Default Branch: master
- Last Pushed: 2018-02-13T16:43:56.000Z (almost 8 years ago)
- Last Synced: 2025-04-13T14:42:41.419Z (8 months ago)
- Topics: arduino, atmega, avr, esp01, esp8266, iot, lcd1602, wifi
- Language: C
- Homepage: http://styczynski.in/avr-weather-esp8266/
- Size: 9.75 MB
- Stars: 16
- Watchers: 3
- Forks: 10
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project
README
# Weather fetching on Atmega32 + ESP8266 + LCD1602
### About
[See the full docs!](http://styczynski.in/avr-weather-esp8266/)
[And also see this on git!](https://github.com/isis97/avr-weather-esp8266)
### Short description
This project tends to implement:
* ESP8266 module messaging from AVR controller
* Basic Http request + JSON parsing
* LCD support
### Why it has been made?
Because of the microcontroller exercises we did on our studies.
### What does it do?
* Boots up (if you press any key) the avr enters
`settings mode` and asks for wifi creditentials
* If no key was pressed during boot then normal procedure takes place
* AVR tries to connect to the wifi
* Then connects to `openweathermap.com`
* Asks politely for weather data for `Warsaw`
* Then fetches `JSON` with the most trivial ways
* Displays the data
* And sometimes refreshes the collected data :)
### Pinout
#### Main wirings
The AVR connections are basic and listed below:
```javascript
'ATMEGA32' PA0 -> D4 'LCD'
'ATMEGA32' PA1 -> D5 'LCD'
'ATMEGA32' PA2 -> D6 'LCD'
'ATMEGA32' PA3 -> D7 'LCD'
'ATMEGA32' PA4 -> RS 'LCD'
'ATMEGA32' PA5 -> RW 'LCD'
'ATMEGA32' PA6 -> E 'LCD'
'ATMEGA32' RXD -> TX 'ESP8266'
'ATMEGA32' TXD -> RX 'ESP8266'
'ESP8266' EN -> VCC 'ESP8266'
```
And of course `V0`, `VCC`, `GND`, `VSS`, `VDD`, `A`, `K` but they are trivial.
#### Buttons
And not mentioned in layout two buttons for settings screen:
```javascript
'ATMEGA32' PD6 -(BUTTON)-> GND
'ATMEGA32' PD7 -(BUTTON)-> GND
```
In settings mode:
* `PD6` is used have next character functionality.
* `PD7` changes current character.
Schematic of connections (pretty small - try to enlarge with zooming hand):
**Notice:**
*The `ESP8266` module was connected to the `5V USB` plug.
The module is designed to work for 3V but working on higher
voltage is possible (as demonstrated in this case).*
*It's straightforward method and in normal conidtions
you should redesign scheme a little and provide 3V voltage source
for your wifi module.*
*You will probably need logic level shifting
form `5V (atemga)` to `3V (esp8266)` or you can just run atmega on 3V
(notice that LCD needs standard 5V anyway!)*
#### Mounting
You can mount the wires propably on pcb plate I used universal brakboard
that does not require soldering but it's rather a messy pile of cables, huh!
### About building
#### Build process
**Warnning!**
*Before building make sure all it's configured correctly (see configuration for more details)!*
To build the project do the following:
* Create release folder e.g. `mkdir release`
* Go into that folder `cd release`
* Run CMAKE to generate needed makefiles `cmake ..`
* Build app using make `make`
* Optionally update documentation throught `make doc`
* Optionally setup manually the needed fuse bits using `avrdude`!
* Flash controller with `make upload`
* Optionally clean build with `make clean`
#### Configuration
Before continouing make sure that `USSID` and `PASSWD` Variables
in `src/main.c` are configured to use with your wifi access point.
Then make sure that `APIKEY` in line with `wifi_send` is matching
apikey for your openweathermap account.
And the url is for location desired by you.
See `openweathermap api documentation` for more details :)
The main controller config is placed in `CMakeLists.txt` file.
Please change these as you wish:
```bash
# Variables regarding the AVR chip
set(MCU atmega32)
set(F_CPU 8000000)
set(BAUD 9600)
set(PROG_TYPE usbasp)
set(PROG_ARGS )
```
`BAUD` is not really needed and `PROG_ARGS` are additional paramters for avrdude.
Basic example config for `Atmega328P-PU` running (by default) at 1MHz:
```bash
# Variables regarding the AVR chip
set(MCU atmega328p)
set(F_CPU 1000000)
set(BAUD 2400)
set(PROG_TYPE usbasp)
set(PROG_ARGS )
```
### Some source code
This snippet presents piece of source code from `main.c`
(and is good introduction to the project insides as well as wifi.h module):
```cpp
// Handle ESP8266 events
void wifi_event_handler(int event, const char* input, const int len) {
switch(event) {
case WIFI_EVENT_ANY: {
//
// You can display the input
// To provide debug info
// This kind of event (ANY)
// is called for any event
//
return;
} break;
case WIFI_EVENT_ERROR: {
// We got error!
} break;
// ESP8266 is not responding
case WIFI_EVENT_TIMEOUT: {
// We got timeout!
} break;
// Wifi was connected
case WIFI_EVENT_WIFI_CONNECTED: {
// We are conneted to the access point!
} break;
// Wifi was disconnected
case WIFI_EVENT_WIFI_DISCONNECTED: {
// We are disconneted to the access point!
} break;
// Connect to host
case WIFI_EVENT_CONNECTED: {
// We are connected to the ip/url specified earlier throug wifi_link_open
} break;
// Host sends data
case WIFI_EVENT_DATA: {
//
// Look for JSON data in response
//
search_json(weather_descr, input, "description");
search_json(weather_name, input, "name");
search_json(weather_data_buf, input, "humidity");
sscanf(weather_data_buf, "%lf", &weather_humidity);
search_json(weather_data_buf, input, "pressure");
sscanf(weather_data_buf, "%d", &weather_pressure);
search_json(weather_data_buf, input, "temp");
sscanf(weather_data_buf, "%lf", &weather_temp);
// We do not need this connection anymore
wifi_link_close();
// Format received data
sprintf(info1, "%s Weather:", weather_name);
sprintf(info2, "%s | Temp: %.1lf C | Humidity: %.0lf %% | Pressure: %d HPa", weather_name, weather_temp-273.15, weather_humidity, weather_pressure );
//
// Display data continously in text shifting manner
//
int shift = 0;
const int info_len = strlen(info2);
int cycles = 0;
while(1) {
lcd_clrscr();
lcd_gotoxy(0, 0);
lcd_nputs(info1, 16);
lcd_gotoxy(0, 1);
lcd_nputs(info2+shift, 16);
_delay_ms(500);
++shift;
if(shift > info_len - 4) {
shift = 0;
++cycles;
}
//
// End - return to main and then prepare next fetch request
//
if(cycles > 15) break;
}
lcd_nputs("Update...", 16);
lcd_clrscr();
} break;
}
}
int main(void) {
// Init UART
uart_init(UART_BAUD_SELECT(2400, F_CPU));
// Init buttons
//
// ...
//
// Init LCD
lcd_init(LCD_DISP_ON);
lcd_gotoxy(0, 0);
lcd_clrscr();
// Init wifi and connect to the desired network
lcd_clrscr();
lcd_puts("Initializing...");
_delay_ms(1000);
wifi_init();
//
// Check if any button was pressed
// then go into settings mode :)
//
//
// ...
//
//
// Normal boot sequence
//
normal_boot:
// Display greeting on lcd
lcd_puts("Hello");
_delay_ms(1000);
lcd_clrscr();
_delay_ms(1500);
lcd_clrscr();
lcd_puts("Conecting...");
_delay_ms(1000);
//
// Display USSID/PASSWD data on the screen
//
lcd_clrscr();
lcd_puts("ID: ");
lcd_puts(USSID);
lcd_puts("\nPASS: ");
lcd_puts(PASSWD);
_delay_ms(1500);
// Try to connect to the access point
wifi_connect(USSID, PASSWD);
while(1) {
// To make sure nothing dumb trash does not come
// through UART interface
uart_flush();
// Connect to openweathermap
wifi_link_open("TCP", "api.openweathermap.org", 80);
// Request data from REST api
wifi_send("GET /data/2.5/weather?q=warsaw&APPID=cf24c94ac2550178e2ea4e970cd0f416 HTTP/1.1\r\nHost: api.openweathermap.org\r\nConnection: keep-alive\r\nCache-Control: max-age=0\r\n\r\n\r\n");
// Wifi functions will call wifi_event_handler function on any event (it's callback function)
}
return 0;
}
```