2.0 KiB
@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)
- A1 [SPI]:
- CANbus Controller 1 (Microchip Technology MCP2515T-I/SO)
- GPS Receiver (U-Blox NEO-M9N [SparkFun Breakout Board])
- A2 [UART]:
- USB to UART Bridge (Future Technology Devices International FT230XS-R)
- A3 [UART]:
- RS-232 Transceiver (Maxim Integrated MAX3232EUE+)
- A0 [SPI]:
-
B - Supporting up to four total of I2C and/or SPI
- B0 [SPI]:
- SD Card
- B1 [I2C]:
- Inertial Measurement Unit (TDK InvenSense ICM-20948)
- B2 [I2C]:
- Real-Time Clock/Calendar (Microchip Technology MCP7940MT-I/SN)
- B3 [SPI]:
- Bluetooth/Wi-Fi (Espressif Systems ESP32-WROVER-IE (8MB))
- B0 [SPI]:
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.