700
edits
Changes
no edit summary
=== Top Sheet ===
=== Top Sheet ===
[[File:oscar_raw.JPG | right| thumb | <center> Oscar PCB </center>]]
The top sheet displays the overarching hierarchy of the avionics board. Only perimeter Teensy pins were utilized, hence pins 24-33 and A10-A14 are NC. The GPS was connected to Hardware Serial 1 over pins 0/1. Pin 2 was driven low when SD card was detected (output of the Micro SD sheet). Pins 3-5 were not utilized. Pins 6-9 were used for RockBlock operation, although NETAV & SLEEP were not used for actual operation, and may be discarded in the future. Pins 10-13 were used to define the SPI Bus, and pin 10 was used as the Micro SD chip select. As seen in the bottom left, pinouts were supplied for I2C and SPI. VIN was supplied with +5V from the boost circuit. Two decoupling caps for +3.3 and +5 were sourced local to the MCU. Pins 22-20 were defined as chip selects for the thermocouple and BMP 280's (22 for thermocouple, 21/20 for BMP280). Pins 19/18 defined the I2C bus. The I2C bus had five total devices: Two MS5803's, One MPL3115A2, One MCP23017 multiplexer, and one RTC IC. Pin 16 connected to the battery protector (LTC4218) power good indicator. Pins 15 and 14 were used for current monitor (via 4218) and battery voltage detection.
The top sheet displays the overarching hierarchy of the avionics board. Only perimeter Teensy pins were utilized, hence pins 24-33 and A10-A14 are NC. The GPS was connected to Hardware Serial 1 over pins 0/1. Pin 2 was driven low when SD card was detected (output of the Micro SD sheet). Pins 3-5 were not utilized. Pins 6-9 were used for RockBlock operation, although NETAV & SLEEP were not used for actual operation, and may be discarded in the future. Pins 10-13 were used to define the SPI Bus, and pin 10 was used as the Micro SD chip select. As seen in the bottom left, pinouts were supplied for I2C and SPI. VIN was supplied with +5V from the boost circuit. Two decoupling caps for +3.3 and +5 were sourced local to the MCU. Pins 22-20 were defined as chip selects for the thermocouple and BMP 280's (22 for thermocouple, 21/20 for BMP280). Pins 19/18 defined the I2C bus. The I2C bus had five total devices: Two MS5803's, One MPL3115A2, One MCP23017 multiplexer, and one RTC IC. Pin 16 connected to the battery protector (LTC4218) power good indicator. Pins 15 and 14 were used for current monitor (via 4218) and battery voltage detection.