The W65C816EDU is a plugin expansion board for the W65C816SXB.  The board is meant to expand the functionality of WDC’s chip products through communication protocols and connectors from SEEED, Sparkfun, and MikroElektronika.

• Designed for W65C816SXB
• All IO pins are 5.0V; same compatibility as W65C816SXB.
• IS61C5128AL-10T – 512KB Parallel SRAM
• 1x SparkFun QWIIC® connector for I2C module expansion
• 5x Seeed Studio Grove connectors for I2C, UART, Analog, and I/O (CB1/2, PB6/7) expansion
• MikroElektronika mikroBUS Click Board connector for I2C, UART, SPI, ADC, PWM, and I/O expansion
• 1x I2C Connector for I2C OLED or other general I2C modules
• CR2032 3.3V Battery holder for Real-Time Clock and Serial SRAM.  Note: battery not included with the board due to shipping restrictions.
• Active Passive Buzzer with toggle switch (Controlled by VIA CA2)
• MCP79411 Real Time Clock
• ATECC608A CryptoAuthentication™ *** Currently unpopulated due to manufacturing availability
• 23LCV1024 – 128KB Serial SRAM with battery backup (SPI) *** Currently unpopulated due to manufacturing availability
• ADS1015 ADC and MCP9700 Temp Sensor *** Currently unpopulated/unusable due to manufacturing availability

Datasheet  Schematic   SEEED Grove Sparkfun QWIIC MikroElektronika Click