Circuit Documentation

Summary of the Circuit

This circuit appears to be designed for interfacing a Wemos D1 Mini microcontroller with various peripherals including an OLED display, an external EEPROM, a port expander (MCP23017), a MIDI connector, multiple pushbuttons, and several LEDs with current-limiting resistors. The Wemos D1 Mini is powered by a 3.3V supply and communicates with the I2C devices (OLED display, EEPROM, and MCP23017). The pushbuttons are likely used for user input, and the LEDs provide visual feedback. The MIDI connector could be used for musical data communication.

Component List

Microcontroller

• Wemos D1 Mini: A compact microcontroller based on the ESP8266, featuring WiFi capabilities and multiple digital I/O pins.

Displays

• OLED 128x64 I2C Monochrome Display: A small display for visual output, interfaced via the I2C protocol.

Memory

• AT24C256 External EEPROM: An I2C-compatible electrically erasable programmable read-only memory chip for additional data storage.

I/O Expanders

• MCP23017: A 16-bit I/O expander with an I2C interface, used to increase the number of I/O pins available to the microcontroller.

Connectors

• MIDI Chassis connector: A standard 5-pin connector used for MIDI (Musical Instrument Digital Interface) communication.

Input Devices

• Pushbuttons: Simple momentary pushbuttons used for user input.

Indicators

• LEDs (red and blue): Light-emitting diodes used as visual indicators, likely to show status or feedback.

Passive Components

• Resistors: Various resistors used for current limiting and pull-up/pull-down configurations.

Wiring Details

Wemos D1 Mini

• 3V3 connected to the power supply lines of the OLED display, EEPROM, and MCP23017.
• G connected to the ground lines of the OLED display, EEPROM, MCP23017, and MIDI connector.
• D2 connected to the SDA lines of the OLED display, EEPROM, and MCP23017.
• D1 connected to the SCL line of the MCP23017.

OLED 128x64 I2C Monochrome Display

• VDD connected to the 3.3V power supply.
• GND connected to the ground.
• SCK connected to the SCL line of the EEPROM.
• SDA connected to the SDA line shared with the Wemos D1 Mini and EEPROM.

AT24C256 External EEPROM

• VCC connected to the 3.3V power supply.
• GND connected to the ground.
• SCL connected to the SCK line of the OLED display.
• SDA connected to the SDA line shared with the Wemos D1 Mini and OLED display.

MCP23017

• VIN connected to the 3.3V power supply.
• GND connected to the ground.
• SCL connected to the D1 pin of the Wemos D1 Mini.
• SDA connected to the D2 pin of the Wemos D1 Mini.
• A0-A5 connected to various pushbuttons through pull-up resistors.
• B1, B4, B5 connected to the cathodes of blue LEDs.
• RST not connected in the provided net list.

MIDI Chassis Connector

• Pin 2 connected to the ground.

Pushbuttons

• One side of each pushbutton connected to the ground.
• The other side of each pushbutton connected to various pins on the MCP23017 through pull-up resistors.

LEDs

• The cathodes of the blue LEDs connected to various pins on the MCP23017.
• The anodes of the blue LEDs connected to the 3.3V power supply through current-limiting resistors.

Resistors

• Several 10kΩ resistors likely used as pull-up resistors for the pushbuttons and I2C lines.
• Several 220Ω resistors likely used as current-limiting resistors for the LEDs.

Documented Code

No code was provided in the input. Typically, this section would include the source code for the microcontroller, with comments explaining the functionality of each part of the code. Since there is no code to document, this section remains empty. If code becomes available, it should be added here with appropriate documentation.