Configuration¶
Microcontroller¶
The microcontroller used is an STM32F405RGT6 [1]. For more information have a look at the STM32F405xx Reference Manual [2].
The following considerations have been taken into account for the microcontroller connections:
- Pins are 5V tolerant except when in analog mode or oscillator mode (for PC14, PC15, PH0 and PH1)
- PC13, PC14, PC15 and PI8 are supplied through the power switch. Since the
switch only sinks a limited amount of current (3 mA), the use of GPIOs PC13
to PC15 and PI8 in output mode is limited:
- The speed should not exceed 2 MHz with a maximum load of 30 pF
- These I/Os must not be used as a current source (e.g. to drive an LED)
| Number | Name | Using | Connected to | Functions |
|---|---|---|---|---|
| 1 | VBAT | Power | 3V3 | Power |
| 2 | PC13 | Input | User button | I/O |
| 3 | PC14 | Output | Serial enable | I/O, OSC32_IN |
| 4 | PC15 | Output | ToF reset | I/O, OSC32_OUT |
| 5 | PH0 | NC | ? HSE crystal | I/O, OSC_IN |
| 6 | PH1 | NC | ? HSE crystal | I/O, OSC_OUT |
| 7 | NRST | Reset | Reset button | Reset |
| 8 | PC0 | ADC123_IN10 | Receiver front right | ADC123_IN10 |
| 9 | PC1 | ADC123_IN11 | Receiver side right | ADC123_IN11 |
| 10 | PC2 | ADC123_IN12 | Receiver side left | SPI2_MISO, ADC123_IN12 |
| 11 | PC3 | ADC123_IN13 | Receiver front left | SPI2_MOSI, ADC123_IN13 |
| 12 | VSSA | Power | AGND | Power |
| 13 | VDDA | Power | A3V3 | Power |
| 14 | PA0 | Output | LED array | USART2_CTS, UART4_TX, TIM2_CH1_ETR, TIM5_CH1, TIM8_ETR, ADC123_IN0 |
| 15 | PA1 | Output | LED array | USART2_RTS, UART4_RX, TIM2_CH2, TIM5_CH2, ADC123_IN1 |
| 16 | PA2 | Output | LED array | USART2_TX, TIM2_CH3, TIM5_CH3, TIM9_CH1, ADC123_IN2 |
| 17 | PA3 | Output | LED array | USART2_RX, TIM2_CH4, TIM5_CH4, TIM9_CH2, ADC123_IN3 |
| 18 | VSS | Power | GND | Power |
| 19 | VDD | Power | 3V3 | Power |
| 20 | PA4 | Output | Emitter front right | SPI1_NSS, SPI3_NSS, USART2_CK, ADC12_IN4 |
| 21 | PA5 | Output | Emitter side right | SPI1_SCK, TIM2_CH1_ETR, TIM8_CH1N, ADC12_IN5 |
| 22 | PA6 | Output | Emitter side left | SPI1_MISO, TIM1_BKIN, TIM3_CH1, TIM8_BKIN, TIM13_CH1, ADC12_IN6 |
| 23 | PA7 | Output | Emitter front left | SPI1_MOSI, TIM1_CH1N, TIM3_CH2, TIM8_CH1N, TIM14_CH1, ADC12_IN7 |
| 24 | PC4 | ADC12_IN14 | Battery voltage (divided) | ADC12_IN14 |
| 25 | PC5 | ADC12_IN15 | Motor voltage (divided) | ADC12_IN15 |
| 26 | PB0 | NC | ? | TIM1_CH2N, TIM3_CH3, TIM8_CH2N, ADC12_IN8 |
| 27 | PB1 | NC | ? | TIM1_CH3N, TIM3_CH4, TIM8_CH3N, ADC12_IN9 |
| 28 | PB2/BOOT1 | Input | GND | I/O |
| 29 | PB10 | I2C2_SCL | ToF sensor SCL | SPI2_SCK, USART3_TX, I2C2_SCL, TIM2_CH3 |
| 30 | PB11 | I2C2_SDA | ToF sensor SDA | USART3_RX, I2C2_SDA, TIM2_CH4 |
| 31 | VCAP1 | Power | To GND through a 2.2uF capacitor | Power |
| 32 | VDD | Power | 3V3 | Power |
| 33 | PB12 | NC | ? | SPI2_NSS, I2C2_SMBA, USART3_CK, TIM1_BKIN |
| 34 | PB13 | NC | ? | SPI2_SCK, USART3_CTS, TIM1_CH1N |
| 35 | PB14 | Output | Gyroscope FSYNC | SPI2_MISO, USART3_RTS, TIM1_CH2N, TIM8_CH2N, TIM12_CH1 |
| 36 | PB15 | Input | Gyroscope INT | SPI2_MOSI, TIM1_CH3N, TIM8_CH3N |
| 37 | PC6 | TIM8_CH1 | Motor driver AIN1 (right) | USART6_TX, TIM3_CH1, TIM8_CH1 |
| 38 | PC7 | TIM8_CH2 | Motor driver AIN2 (right) | USART6_RX, TIM3_CH2, TIM8_CH2 |
| 39 | PC8 | TIM8_CH3 | Motor driver BIN1 (left) | USART6_CK, TIM3_CH3, TIM8_CH3 |
| 40 | PC9 | TIM8_CH4 | Motor driver BIN2 (left) | I2C3_SDA, TIM3_CH4, TIM8_CH4 |
| 41 | PA8 | USART1_CK | Serial CK | USART1_CK, TIM1_CH1, I2C3_SCL |
| 42 | PA9 | USART1_TX | Serial RX | USART1_TX, TIM1_CH2, I2C3_SMBA |
| 43 | PA10 | USART1_RX | Serial TX | USART1_RX, TIM1_CH3 |
| 44 | PA11 | USART1_CTS | Serial RTS | USART1_CTS, TIM1_CH4 |
| 45 | PA12 | USART1_RTS | Serial CTS | USART1_RTS, TIM1_ETR |
| 46 | PA13 | SWDIO | Programmer SWDIO pin | JTMS-SWDIO |
| 47 | VCAP2 | Power | To GND through a 2.2uF capacitor | Power |
| 48 | VDD | Power | 3V3 | Power |
| 49 | PA14 | SWCLK | Programmer SWCLK pin | JTCK-SWCLK |
| 50 | PA15 | SPI3_NSS | Gyroscope NCS (SPI-CS) | JTDI, SPI1_NSS, SPI3_NSS, TIM2_CH1_ETR |
| 51 | PC10 | SPI3_SCK | Gyroscope SCL (SPI-SCLK) | USART3_TX, UART4_TX, SPI3_SCK |
| 52 | PC11 | SPI3_MISO | Gyroscope AD0 (SPI-SDO) | USART3_RX, UART4_RX, SPI3_MISO |
| 53 | PC12 | SPI3_MOSI | Gyroscope SDA (SPI-SDI) | USART3_CK, UART5_TX, SPI3_MOSI |
| 54 | PD2 | NC | ? | UART5_RX, TIM3_ETR |
| 55 | PB3 | NC | ? | JTDO, TRACESWO, SPI1_SCK, SPI3_SCK, TIM2_CH2 |
| 56 | PB4 | TIM3_CH1 | Encoder left, channel A | NJTRST, SPI1_MISO, SPI3_MISO, TIM3_CH1 |
| 57 | PB5 | TIM3_CH2 | Encoder left, channel B | SPI1_MOSI, SPI3_MOSI, I2C1_SMBA, TIM3_CH2 |
| 58 | PB6 | TIM4_CH1 | Encoder right, channel B | USART1_TX, I2C1_SCL, TIM4_CH1 |
| 59 | PB7 | TIM4_CH2 | Encoder right, channel A | USART1_RX, I2C1_SDA, TIM4_CH2 |
| 60 | BOOT0 | BOOT0 | GND/3V3 jumper (default GND) | BOOT0 |
| 61 | PB8 | TIM10_CH1 | Fan driver | I2C1_SCL, TIM4_CH3, TIM10_CH1 |
| 62 | PB9 | TIM11_CH1 | Speaker signal | SPI2_NSS, I2C1_SDA, TIM4_CH4, TIM11_CH1 |
| 63 | VSS | Power | GND | Power |
| 64 | VDD | Power | 3V3 | Power |
Encoders¶
Timers 3 and 4 are configured to read quadrature encoders (and thus, connected to the IE2-1024 encoder [3] channels A and B). They are both configured to count on both TI1 and TI2 edges.
Gyroscope¶
Gyros are selected as the clock source for accuracy (versus the internal relaxation oscillator suitable for lower power consumption when only accelerometer is being used).
The MPU-6500 gyro features the following SPI operational features:
- Data is delivered MSB first and LSB last.
- Data is latched on the rising edge of SCLK.
- Data should be transitioned on the falling edge of SCLK.
- The maximum frequency of SCLK is 1 MHz. Although the sensor and interrupt registers may be read using SPI at 20 MHz.
- Read/write operations are completed in 16+ cycles (2+ bytes).
- First byte contains the SPI address, and the following the SPI data.
- First bit of the first byte contains the Read (1) / Write (0) bit.
- The following 7 bits contain the Register Address.
- In cases of multiple-byte read/writes, data is two or more bytes.
