Chapter 8. Advanced Experiments
8.4. Experiment with 24C01 EEPROM
The AT24C01 provides 1024 bits of serial electrically erasable and programmable read-only memory (EEPROM) organized as 128 words of 8 bits each. The device is optimized for use in many industrial and commercial applications where low-power and low-voltage operation are essential. The AT24C01 is available in space-saving 8-lead PDIP, 8-lead JEDEC SOIC, 8-lead Ultra Thin Mini-MAP (MLP 2x3), 5-lead SOT23 , 8-lead TSSOP, and 8-ball dBGA2 packages and is accessed via a Two-wire serial interface. In addition, the entire family is available in 2.7V (2.7V to 5.5V) and 1.8V (1.8V to 5.5V) versions.
SCL: The SCL input is used to positive edge clock data into each EEPROM device and negative edge clock data out of each device.
SDA: The SDA pin is bidirectional for serial data transfer. This pin is open-drain driven and may be wire-ORed with any number of other open-drain or open-collector devices.
A2, A1, A0: The A2, A1 and A0 pins are device address inputs that are hard wired for the AT24C01.
WP: The AT24C01 has a Write Protect pin that provides hardware data protection. The Write Protect pin allows normal Read/Write operations when connected to ground (GND). When the Write Protect pin is connected to VCC, the write protection feature is enabled and operates as shown in Table 2.
VCC：Power supply, +5V.
The experiment illustrates the I2C communication between MCU and 24C01 EEPROM. Data 0x55 and 0xAA are written to EEPROM at memory address 0x01 and 0x02. The data read from EEPROM will be displayed on LED display. By default, the address to be read is 0x02, user can change the address.
Toggle on the function select to ‘24D**’ before this experiment.