墨星stm32快速参考

moxing stm32 pinout

通用硬件控制

See pyb.

import pyb

pyb.repl_uart(pyb.UART(2, 9600)) # duplicate REPL on UART(2)在UART（2）上重置REPL
pyb.wfi() # pause CPU, waiting for interrupt 暂停cpu，等待中断
pyb.freq() # get CPU and bus frequencies 获得CPU频率
pyb.freq(60000000) # set CPU freq to 60MHz 设置CPU频率
pyb.stop() # stop CPU, waiting for external interrupt 停止cpu，等待外部中断

延时和时间

Use the time module:

import time

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

Pins and GPIO

See pyb.Pin.

from pyb import Pin

p_out = Pin('P1', Pin.OUT_PP)
p_out.high()
p_out.low()

p_in = Pin('P2', Pin.IN, Pin.PULL_UP)
p_in.value() # get value, 0 or 1

外部中断

See pyb.ExtInt.

from pyb import Pin, ExtInt

callback = lambda e: print("intr")
ext = ExtInt(Pin('P1'), ExtInt.IRQ_RISING, Pin.PULL_UP, callback)

定时器

See pyb.Timer.

from pyb import Timer

tim = Timer(1, freq=1000)
tim.counter() # get counter value 获取计时器值
tim.freq(0.5) # 0.5 Hz
tim.callback(lambda t: print('count'))

PWM脉宽调制

See pyb.Pin and pyb.Timer.

from pyb import Pin, Timer

p = Pin('P1') # P1 has TIM1, CH2N
tim = Timer(1, freq=1000)
ch = tim.channel(2, Timer.PWM, pin=p)
ch.pulse_width_percent(50)

ADC (模数转换)

See pyb.Pin and pyb.ADC.

from pyb import Pin, ADC

adc = ADC(Pin('A1'))
adc.read() # read value,读取值 0-4095

DAC (数模转换)

See pyb.Pin and pyb.DAC.

from pyb import Pin, DAC

dac = DAC(Pin('A2'))
dac.write(120) # 输出介于0-255

UART (串行总线)

See pyb.UART.

from pyb import UART

uart = UART(1, 9600)
uart.write('hello')
uart.read(5) # read up to 5 bytes 读取5个字节

SPI总线

See pyb.SPI.

from pyb import SPI

spi = SPI(2, SPI.MASTER, baudrate=200000, polarity=1, phase=0)
spi.send('hello')
spi.recv(5) # receive 5 bytes on the bus 在总线上接收5个字节
spi.send_recv('hello') # send and receive 5 bytes 发送5个字节

I2C bus

See pyb.I2C.

from pyb import I2C

i2c = I2C(2, I2C.MASTER, baudrate=100000)
i2c.scan() # returns list of slave addresses 返回一个从属设备地址的列表
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
i2c.recv(5, 0x42) # receive 5 bytes from slave 从从属设备上接收5个字节
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
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