OpenMV Cam快速参考

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OpenMV Cam快速参考通用硬件控制

See pyb.

1. import pyb
   
2. 
   
3. pyb.repl_uart(pyb.UART(3, 9600, timeout_char=1000)) # duplicate REPL on UART(3) 在UART（3）上重置REPL
   
4. pyb.wfi() # pause CPU, waiting for interrupt 暂停cpu，等待中断
   
5. pyb.stop() # stop CPU, waiting for external interrupt 停止cpu，等待外部中断

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延时和时间

Use the time module:

1. import utime
   
2. 
   
3. time.sleep(1)           # sleep for 1 second 延时1s
   
4. time.sleep_ms(500)      # sleep for 500 milliseconds 延时500ms
   
5. time.sleep_us(10)       # sleep for 10 microseconds 延时10us
   
6. start = time.ticks_ms() # get value of millisecond counter  获取毫秒计数器的值
   
7. delta = time.ticks_diff(time.ticks_ms(), start) # compute time difference 计算时间差

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LED 发光二极管

See pyb.LED.

1. from pyb import LED
   
2. 
   
3. led = LED(1) # 红色 led
   
4. led.toggle()
   
5. led.on()
   
6. led.off()

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LED Pinout:

• LED(1) -> 红色 RGB LED Segment
• LED(2) -> 绿色 RGB LED Segment
• LED(3) -> 蓝色 RGB LED Segment
• LED(4) -> 红外 LEDs
  

引脚和GPIO

See pyb.Pin.

1. from pyb import Pin
   
2. 
   
3. p_out = Pin('P7', Pin.OUT_PP)
   
4. p_out.high()
   
5. p_out.low()
   
6. 
   
7. p_in = Pin('P8', Pin.IN, Pin.PULL_UP)
   
8. p_in.value() # get value, 0 or 1

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GPIO引脚分配:

• Pin(‘P0’) -> P0 (PB15)
• Pin(‘P1’) -> P1 (PB14)
• Pin(‘P2’) -> P2 (PB13)
• Pin(‘P3’) -> P3 (PB12)
• Pin(‘P4’) -> P4 (PB10)
• Pin(‘P5’) -> P5 (PB11)
• Pin(‘P6’) -> P6 (PA5)
• Pin(‘P7’) -> P7 (PD12)
• Pin(‘P8’) -> P8 (PD13)
• Pin(‘P9’) -> P9 (PD14) (只在OpenMV Cam M7/H7)
  

所有引脚适配范围为5V，其输出为3V（在ADC或DAC模式下，P6的适配范围并不是5V）。

所有引脚最高输入或者输出25mA（所有引脚加起来最高120mA）。

舵机控制

见 pyb.Servo.

1. from pyb import Servo
   
2. 
   
3. s1 = Servo(1) # servo on position 1 (P7) 位置1的servo（P7）
   
4. s1.angle(45) # move to 45 degrees 移动到45度
   
5. s1.angle(-60, 1500) # move to -60 degrees in 1500ms 在1500ms内移动到-60度
   
6. s1.speed(50) # for continuous rotation servos 连续旋转舵机

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Servo Pinout:

• Servo(1) -> P7 (PD12)
• Servo(2) -> P8 (PD13)
• Servo(3) -> P9 (PD14) (OpenMV Cam M7/H7 Only)
  

外部中断

See pyb.ExtInt.

1. from pyb import Pin, ExtInt
   
2. 
   
3. callback = lambda e: print("intr")
   
4. ext = ExtInt(Pin('P7'), ExtInt.IRQ_RISING, Pin.PULL_NONE, callback)

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GPIO Pinout:

• Pin(‘P0’) -> P0 (PB15)
• Pin(‘P1’) -> P1 (PB14)
• Pin(‘P2’) -> P2 (PB13)
• Pin(‘P3’) -> P3 (PB12)
• Pin(‘P4’) -> P4 (PB10)
• Pin(‘P5’) -> P5 (PB11)
• Pin(‘P6’) -> P6 (PA5)
• Pin(‘P7’) -> P7 (PD12)
• Pin(‘P8’) -> P8 (PD13)
• Pin(‘P9’) -> P9 (PD14) (只在OpenMV Cam M7/H7)
  

定时器

See pyb.Timer.

1. from pyb import Timer
   
2. 
   
3. tim = Timer(4, freq=1000)
   
4. tim.counter() # get counter value 获取计时器值
   
5. tim.freq(0.5) # 0.5 Hz
   
6. tim.callback(lambda t: pyb.LED(1).toggle())

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定时器引脚分配：

• Timer 1 Channel 3 Negative -> P0 (PB15)
• Timer 1 Channel 2 Negative -> P1 (PB14)
• Timer 1 Channel 1 Negative -> P2 (PB13)
• Timer 2 Channel 3 Positive -> P4 (PB10)
• Timer 2 Channel 4 Positive -> P5 (PB11)
• Timer 2 Channel 1 Positive -> P6 (PA5)
• Timer 4 Channel 1 Negative -> P7 (PD12)
• Timer 4 Channel 2 Negative -> P8 (PD13)
• Timer 4 Channel 3 Positive -> P9 (PD14) (OpenMV Cam M7/H7 Only)
  

PWM脉宽调制

See pyb.Pin and pyb.Timer.

1. from pyb import Pin, Timer
   
2. 
   
3. p = Pin('P7') # P7 has TIM4, CH1
   
4. tim = Timer(4, freq=1000)
   
5. ch = tim.channel(1, Timer.PWM, pin=p)
   
6. ch.pulse_width_percent(50)

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定时器引脚分配：

• Timer 1 Channel 3 Negative -> P0 (PB15)
• Timer 1 Channel 2 Negative -> P1 (PB14)
• Timer 1 Channel 1 Negative -> P2 (PB13)
• Timer 2 Channel 3 Positive -> P4 (PB10)
• Timer 2 Channel 4 Positive -> P5 (PB11)
• Timer 2 Channel 1 Positive -> P6 (PA5)
• Timer 4 Channel 1 Negative -> P7 (PD12)
• Timer 4 Channel 2 Negative -> P8 (PD13)
• Timer 4 Channel 3 Positive -> P9 (PD14) (OpenMV Cam M7/H7 Only)
  

ADC (模数转换)

见 pyb.Pin 和 pyb.ADC.

1. from pyb import Pin, ADC
   
2. 
   
3. adc = ADC(Pin('P6'))
   
4. adc.read() # read value, 0-4095 读取值，0-4095

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ADC 引脚分配:

• ADC(Pin(‘P6’)) -> P6 (PA5)
  

ADC模式下，P6的适配范围为3.3V，而不是5V！

DAC (数模转换)

见 pyb.Pin and pyb.DAC.

1. from pyb import Pin, DAC
   
2. 
   
3. dac = DAC('P6')
   
4. dac.write(120) # 输出介于0-255

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DAC 引脚分配:

• DAC(Pin(‘P6’)) -> P6 (PA5)
  

DAC模式下，P6的适配范围为3.3V，而不是5V！

UART (串行总线)

See pyb.UART.

1. from pyb import UART
   
2. 
   
3. uart = UART(3, 9600, timeout_char=1000)
   
4. uart.write('hello')
   
5. uart.read(5) # read up to 5 bytes 读取5个字节

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UART Pinout:

• UART 3 RX -> P5 (PB11)
• UART 3 TX -> P4 (PB10)
• UART 1 RX -> P0 (PB15) (只在OpenMV Cam M7/H7)
• UART 1 TX -> P1 (PB14) (只在OpenMV Cam M7/H7)
  

SPI总线

见 pyb.SPI.

1. from pyb import SPI
   
2. 
   
3. spi = SPI(2, SPI.MASTER, baudrate=1000000, polarity=1, phase=0)
   
4. spi.send('hello')
   
5. spi.recv(5) # receive 5 bytes on the bus 在总线上接收5个字节
   
6. spi.send_recv('hello') # send a receive 5 bytes 发送5个字节

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SPI 引脚分配:

• SPI 2 MOSI (Master-Out-Slave-In) -> P0 (PB15)
• SPI 2 MISO (Master-In-Slave-Out) -> P1 (PB14)
• SPI 2 SCLK (Serial Clock) -> P2 (PB13)
• SPI 2 SS (Serial Select) -> P3 (PB12)
  

I2C总线

See pyb.I2C.

1. from pyb import I2C
   
2. 
   
3. i2c = I2C(2, I2C.MASTER, baudrate=100000)
   
4. i2c.scan() # returns list of slave addresses 返回一个从属设备地址的列表
   
5. i2c.send('hello', 0x42) # send 5 bytes to slave with address 0x42 使用0x42地址向从属设备发送5个字节
   
6. i2c.recv(5, 0x42) # receive 5 bytes from slave 从从属设备上接收5个字节
   
7. i2c.mem_read(2, 0x42, 0x10) # read 2 bytes from slave 0x42, slave memory 0x10 从地址为0x42从属设备上接收2个字节，从属存储器为0x10
   
8. i2c.mem_write('xy', 0x42, 0x10) # write 2 bytes to slave 0x42, slave memory 0x10 向地址为0x42的从属设备写入2个字节，从属存储器为0x10

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I2C 引脚分配:

• I2C 2 SCL (Serial Clock) -> P4 (PB10)
• I2C 2 SDA (Serial Data) -> P5 (PB11)
• I2C 4 SCL (Serial Clock) -> P7 (PD13) (OpenMV Cam M7/H7 Only)
• I2C 4 SDA (Serial Data) -> P8 (PD12) (OpenMV Cam M7/H7 Only)