YACWC

2026-08-31 22:43:51 -04:00
commit c87308caca
521 changed files with 141326 additions and 0 deletions
@@ -0,0 +1,142 @@
+#include "i2c.h"
+#include <util/twi.h>
+
+void i2c_init()
+{
+    // Set SCL and SDA as inputs (automatically done by TWI hardware)
+    TWSR = 0; // Prescaler = 1
+    TWBR = (uint8_t)((F_CPU / F_SCL - 16) / 2); // Set bitrate register
+    TWCR = (1 << TWEN);
+}
+
+// Start i2c communication
+uint8_t i2c_start(uint8_t address)
+{
+    TWCR = (1 << TWSTA) | (1 << TWINT) | (1 << TWEN); // Send START condition
+    while (!(TWCR & (1 << TWINT)))
+        ; // Wait for TWINT flag to be set
+    TWDR = address; // Load address into data register
+
+    TWCR = (1 << TWINT) | (1 << TWEN); // Send address
+    while (!(TWCR & (1 << TWINT)))
+        ; // Wait for TWINT flag to be set
+    uint8_t status = TWSR & 0xF8;
+    if (status != 0x18 && status != 0x40)
+        return 1;
+    return 0;
+    //    return (TWSR & 0xF8); // Return the status code (check if ACK
+    //    received)
+}
+
+uint8_t write_one_byte(uint8_t device_addr, uint8_t register_addr, uint8_t data)
+{
+    return write_n_bytes(device_addr, register_addr, &data, 1);
+}
+
+uint8_t write_n_bytes(uint8_t device_addr, uint8_t register_addr, uint8_t* data, uint8_t n_bytes)
+{
+    I2C_START_WRITE(device_addr);
+    i2c_write(register_addr);
+    for (uint8_t i = 0; i < n_bytes; i++) {
+        i2c_write(data[i]);
+    }
+    i2c_stop();
+    return 0;
+}
+
+uint8_t read_one_byte_no_err_register(uint8_t device_addr, uint8_t register_addr)
+{
+    uint8_t data;
+    read_one_byte(device_addr, register_addr, &data);
+    return data;
+}
+
+uint8_t read_one_byte(uint8_t device_addr, uint8_t register_addr, uint8_t* data)
+{
+    return read_n_bytes(device_addr, register_addr, data, 1);
+}
+
+uint8_t read_n_bytes(uint8_t device_addr, uint8_t register_addr, uint8_t* data, uint8_t n_bytes)
+{
+
+    I2C_START_WRITE(device_addr);
+    i2c_write(register_addr);
+    I2C_START_READ(device_addr);
+
+    for (uint8_t i = 0; i < (n_bytes - 1); i++) {
+        data[i] = i2c_read_ack();
+    }
+
+    data[n_bytes - 1] = i2c_read_nack();
+    i2c_stop();
+
+    return 0;
+}
+
+uint8_t read_one_byte_16bit_addr_no_err_register(uint8_t device_addr, uint16_t register_addr)
+{
+    uint8_t data;
+    read_one_byte_16bit_addr(device_addr, register_addr, &data);
+    return data;
+}
+
+uint8_t read_one_byte_16bit_addr(uint8_t device_addr, uint16_t register_addr, uint8_t* data)
+{
+    return read_n_bytes_16bit_addr(device_addr, register_addr, data, 1);
+}
+
+uint8_t
+read_n_bytes_16bit_addr(uint8_t device_addr, uint16_t register_addr, uint8_t* data, uint8_t n_bytes)
+{
+
+    I2C_START_WRITE(device_addr);
+    //    i2c_write(0xAE);
+    i2c_write(register_addr >> 8);
+    i2c_write(register_addr & 0xFF);
+    I2C_START_READ(device_addr);
+
+    for (uint8_t i = 0; i < (n_bytes - 1); i++) {
+        data[i] = i2c_read_ack();
+    }
+
+    data[n_bytes - 1] = i2c_read_nack();
+    i2c_stop();
+
+    return 0;
+}
+
+// Stop i2c communication
+void i2c_stop()
+{
+    TWCR = (1 << TWSTO) | (1 << TWINT) | (1 << TWEN); // Send STOP condition
+    while (!(TWCR & (1 << TWSTO)))
+        ; // Wait for STOP to complete
+}
+
+uint8_t i2c_read_ack()
+{
+    TWCR = (1 << TWEN) | (1 << TWINT) | (1 << TWEA);
+    while (!(TWCR & (1 << TWINT)))
+        ; // Wait for TWINT flag to be set
+    return TWDR;
+}
+
+uint8_t i2c_write(uint8_t data)
+{
+    // Load data into TWDR
+    TWDR = data;
+    TWCR = (1 << TWEN) | (1 << TWINT);
+    while (!(TWCR & (1 << TWINT)))
+        ; // Wait for TWINT flag set
+    if ((TWSR & 0xF8) != TW_MT_DATA_ACK)
+        return 1; // Check ACK
+    return 0;
+}
+
+uint8_t i2c_read_nack()
+{
+    TWCR = (1 << TWEN) | (1 << TWINT);
+    while (!(TWCR & (1 << TWINT)))
+        ; // Wait for TWINT flag to be set
+    return TWDR;
+}