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-rw-r--r--esp8266/scripts/onewire.py127
1 files changed, 0 insertions, 127 deletions
diff --git a/esp8266/scripts/onewire.py b/esp8266/scripts/onewire.py
deleted file mode 100644
index 686616950a..0000000000
--- a/esp8266/scripts/onewire.py
+++ /dev/null
@@ -1,127 +0,0 @@
-# 1-Wire driver for MicroPython on ESP8266
-# MIT license; Copyright (c) 2016 Damien P. George
-
-import _onewire as _ow
-
-class OneWireError(Exception):
- pass
-
-class OneWire:
- SEARCH_ROM = const(0xf0)
- MATCH_ROM = const(0x55)
- SKIP_ROM = const(0xcc)
-
- def __init__(self, pin):
- self.pin = pin
- self.pin.init(pin.OPEN_DRAIN)
-
- def reset(self):
- return _ow.reset(self.pin)
-
- def readbit(self):
- return _ow.readbit(self.pin)
-
- def readbyte(self):
- return _ow.readbyte(self.pin)
-
- def read(self, count):
- buf = bytearray(count)
- for i in range(count):
- buf[i] = _ow.readbyte(self.pin)
- return buf
-
- def writebit(self, value):
- return _ow.writebit(self.pin, value)
-
- def writebyte(self, value):
- return _ow.writebyte(self.pin, value)
-
- def write(self, buf):
- for b in buf:
- _ow.writebyte(self.pin, b)
-
- def select_rom(self, rom):
- self.reset()
- self.writebyte(MATCH_ROM)
- self.write(rom)
-
- def scan(self):
- devices = []
- diff = 65
- rom = False
- for i in range(0xff):
- rom, diff = self._search_rom(rom, diff)
- if rom:
- devices += [rom]
- if diff == 0:
- break
- return devices
-
- def _search_rom(self, l_rom, diff):
- if not self.reset():
- return None, 0
- self.writebyte(SEARCH_ROM)
- if not l_rom:
- l_rom = bytearray(8)
- rom = bytearray(8)
- next_diff = 0
- i = 64
- for byte in range(8):
- r_b = 0
- for bit in range(8):
- b = self.readbit()
- if self.readbit():
- if b: # there are no devices or there is an error on the bus
- return None, 0
- else:
- if not b: # collision, two devices with different bit meaning
- if diff > i or ((l_rom[byte] & (1 << bit)) and diff != i):
- b = 1
- next_diff = i
- self.writebit(b)
- if b:
- r_b |= 1 << bit
- i -= 1
- rom[byte] = r_b
- return rom, next_diff
-
- def crc8(self, data):
- return _ow.crc8(data)
-
-class DS18B20:
- CONVERT = const(0x44)
- RD_SCRATCH = const(0xbe)
- WR_SCRATCH = const(0x4e)
-
- def __init__(self, onewire):
- self.ow = onewire
-
- def scan(self):
- return [rom for rom in self.ow.scan() if rom[0] == 0x28]
-
- def convert_temp(self):
- if not self.ow.reset():
- raise OneWireError
- self.ow.writebyte(SKIP_ROM)
- self.ow.writebyte(CONVERT)
-
- def read_scratch(self, rom):
- if not self.ow.reset():
- raise OneWireError
- self.ow.select_rom(rom)
- self.ow.writebyte(RD_SCRATCH)
- buf = self.ow.read(9)
- if self.ow.crc8(buf):
- raise OneWireError
- return buf
-
- def write_scratch(self, rom, buf):
- if not self.ow.reset():
- raise OneWireError
- self.ow.select_rom(rom)
- self.ow.writebyte(WR_SCRATCH)
- self.ow.write(buf)
-
- def read_temp(self, rom):
- buf = self.read_scratch(rom)
- return (buf[1] << 8 | buf[0]) / 16