from machine import Pin class MAX7219: REG_NOOP = 0x00 REG_DIGIT0 = 0x01 REG_DIGIT1 = 0x02 REG_DIGIT2 = 0x03 REG_DIGIT3 = 0x04 REG_DIGIT4 = 0x05 REG_DIGIT5 = 0x06 REG_DIGIT6 = 0x07 REG_DIGIT7 = 0x08 REG_DECODE = 0x09 REG_INTENSITY = 0x0A REG_SCANLIMIT = 0x0B REG_SHUTDOWN = 0x0C REG_DISPLAYTEST= 0x0F def __init__(self,spi,cs,num=1): self.spi = spi self.cs = cs self.num = num self.cs.init(Pin.OUT,value=1) self._row_buffer = [0] * 8 self.init() def _write(self,reg,data): self.cs.value(0) self.spi.write(bytes([reg,data])) self.cs.value(1) def init(self): self._write(self.REG_DECODE,0) self._write(self.REG_SCANLIMIT,7) self._write(self.REG_DISPLAYTEST,0) self._write(self.REG_INTENSITY, 8) self.shutdown(False) def shutdown(self,state): self._write(self.REG_SHUTDOWN, 0 if state else 1) def brightness(self,level): self._write(self.REG_INTENSITY,level & 0x0F) def clear(self): self._row_buffer = [0] * 8 for y in range(8): self._write(self.REG_DIGIT0 + y,0) def _reverse_bytes(self,b): b = (b & 0xF0) >> 4 | (b & 0x0F) << 4 b = (b & 0xCC) >> 2 | (b & 0x33) << 2 b = (b & 0xAA) >> 1 | (b & 0x55) << 1 return b def display(self, font): if len(font) != 8: raise ValueError("8×8字模必须是8字节") self.clear() for i in range(8): data = self._reverse_bytes(font[i]) self._write(self.REG_DIGIT0 + i,data) self._row_buffer[i] = data def pixel(self,x,y,state): if x < 0 or x > 7 or y < 0 or y > 7: return if state: self._row_buffer[y] |= (1 << (7-x)) else: self._row_buffer[y] &= ~(1 << (7-x)) self._write(self.REG_DIGIT0 + y,self._row_buffer[y])