Blank I2C output ESP32 simple program #910
Description
Chip type: esp32 (revision v1.0)
Crystal frequency: 40MHz
Flash size: 4MB
Peripheral: MLX90614
VCC: 3V3
GND: GND
SDA: GPIO 21
SCL: GPIO 22
Thank you for the awesome library. I am having issues connecting a MLX90614 (on a breakout board with 4.7K pull-up resistors on sda and scl) to my ESP32.
I've been able to validate that the device works via the Ardunio IDE using this library and this program.
#include <Adafruit_MLX90614.h>
Adafruit_MLX90614 mlx = Adafruit_MLX90614();
void setup() {
Serial.begin(115200);
while (!Serial);
if (!mlx.begin()) {
Serial.println("Error connecting to MLX sensor. Check wiring.");
while (1);
};
}
void loop() {
Serial.print("Ambient temperature = ");
Serial.print(mlx.readAmbientTempC());
Serial.print("°C");
Serial.print(" ");
Serial.print("Object temperature = ");
Serial.print(mlx.readObjectTempC());
Serial.println("°C");
Serial.println("-----------------------------------------------------------------");
delay(500);
}However I cannot seem to get a useful response when trying to communicate with the I2C bus via esp-hal
I've tried to manually write_read at the address 0x5A and always get a response of [ff, ff, ff].
Additionally I've attempted to scan for all I2C devices and send all 1 byte messages and always get a response of [00, 00, 00] or [ff, ff, ff]. Please see the example code below.
I am an embedded newbie so its very likely I'm doing something (or everything) completely wrong. Is there a better/correct way to read data from an I2C bus?
#![no_std]
#![no_main]
use esp32_hal::{
clock::{ClockControl, Clocks},
entry,
gpio::{Gpio6, GpioPin, Output, PushPull, Unknown, IO},
i2c::I2C,
interrupt,
peripherals::{Peripherals, I2C0, I2C1, RTC_I2C},
prelude::*,
Delay,
};
use esp_backtrace as _;
use esp_println::println;
#[entry]
fn main() -> ! {
let peripherals = Peripherals::take();
let system = peripherals.SYSTEM.split();
let clocks = ClockControl::boot_defaults(system.clock_control).freeze();
let io = IO::new(peripherals.GPIO, peripherals.IO_MUX);
let sda = io.pins.gpio21;
let scl = io.pins.gpio22;
let mut i2c = I2C::new(peripherals.I2C0, sda, scl, 100u32.kHz(), &clocks);
for addr in 0..=127 {
if let Ok(_) = i2c.write(addr, &[0x07]) {
println!("Found device at address: 0x{:02X}", addr);
for msg in 0..=255 {
let to_send: [u8; 1] = [msg];
let mut data = [0u8; 3];
i2c.write_read(addr, &to_send, &mut data).ok();
println!("Sent: 0x{:02X}, Received: {:02x?}", msg, data);
}
}
}
loop {}
}