@page designChoices Design Choices

# JTAG Interface

When connecting the MCU to the programmer via the JTAG interface, it is possible for a local power supply connected to the MCU to be used or for power from the debugging/programming adapter to be used. Since having power supplied to the MCU from the debugging/programming adapter can be useful for use outside of the Sunseeker vehicle, we chose to use that.



# Microcontroller Connections

The board is going to be organized to the best of our abilities to be organized as such:

- Left Side:
  - Peripherals for communicating with/controlling the Sunseeker vehicle
- Right Side:
  - Peripherals for communicating with users



#### Universal Serial Communication Interfaces (USCIs):

- A - Supporting up to four total of UART and/or SPI
  - A0 [SPI]:
    - CANbus Controller 0 (Microchip Technology MCP2515T-I/SO)
    - CANbus Controller 1 (Microchip Technology MCP2515T-I/SO)
  - A1:
  - A2 [UART]:
    - USB to UART Bridge (Future Technology Devices International FT230XS-R)
  - A3 [UART]:
    - RS-232 Transceiver (STMicroelectronics ST232CDR)

- B - Supporting up to four total of I2C and/or SPI
  - B0 [SPI]:
    - SD Card
    - GPS Receiver (Maxim Integrated ‎MAX2771ETI+T)
  - B1 [I2C]:
    - Inertial Measurement Unit (TDK InvenSense ICM-20600)
    - Real-Time Clock/Calendar (Microchip Technology ‎MCP7940MT-I/SN)
  - B2:
  - B3 [SPI]:
    - Bluetooth/Wi-Fi (Espressif Systems ESP32-WROVER-IE (8MB))



In addition to trying to keep the MCU and PCB organized with the left-side being to do with the Sunseeker vehicle and the right side to be peripherals interacting with users, we tried to also load-balance the USCI modules, as well as have the SPI protocol be used in more high data-rate peripherals and I2C used with lower or less-used peripherals. In Texas Instruments SLAS655G Document [Page 7] has a pin diagram showing the physical location of where each pin is physically located.