From a065d786753b83ab92873b90d8d61d9fe5639fdd Mon Sep 17 00:00:00 2001 From: Damien George Date: Thu, 22 Jun 2017 16:28:07 +1000 Subject: drivers/onewire: Move onewire.py, ds18x20.py from esp8266 to drivers. These drivers can now be used by any port (so long as that port has the _onewire driver from extmod/modonewire.c). These drivers replace the existing 1-wire and DS18X20 drivers in the drivers/onewire directory. The existing ones were pyboard-specific and not very efficient nor minimal (although the 1-wire driver was written in pure Python it only worked at large enough CPU frequency). This commit brings backwards incompatible API changes to the existing 1-wire drivers. User code should be converted to use the new drivers, or check out the old version of the code and keep a local copy (it should continue to work unchanged). --- esp8266/modules/ds18x20.py | 51 ---------------------------------------------- 1 file changed, 51 deletions(-) delete mode 100644 esp8266/modules/ds18x20.py (limited to 'esp8266/modules/ds18x20.py') diff --git a/esp8266/modules/ds18x20.py b/esp8266/modules/ds18x20.py deleted file mode 100644 index bf06094835..0000000000 --- a/esp8266/modules/ds18x20.py +++ /dev/null @@ -1,51 +0,0 @@ -# DS18x20 temperature sensor driver for MicroPython. -# MIT license; Copyright (c) 2016 Damien P. George - -from micropython import const - -_CONVERT = const(0x44) -_RD_SCRATCH = const(0xbe) -_WR_SCRATCH = const(0x4e) - -class DS18X20: - def __init__(self, onewire): - self.ow = onewire - self.buf = bytearray(9) - - def scan(self): - return [rom for rom in self.ow.scan() if rom[0] == 0x10 or rom[0] == 0x28] - - def convert_temp(self): - self.ow.reset(True) - self.ow.writebyte(self.ow.SKIP_ROM) - self.ow.writebyte(_CONVERT) - - def read_scratch(self, rom): - self.ow.reset(True) - self.ow.select_rom(rom) - self.ow.writebyte(_RD_SCRATCH) - self.ow.readinto(self.buf) - if self.ow.crc8(self.buf): - raise Exception('CRC error') - return self.buf - - def write_scratch(self, rom, buf): - self.ow.reset(True) - self.ow.select_rom(rom) - self.ow.writebyte(_WR_SCRATCH) - self.ow.write(buf) - - def read_temp(self, rom): - buf = self.read_scratch(rom) - if rom[0] == 0x10: - if buf[1]: - t = buf[0] >> 1 | 0x80 - t = -((~t + 1) & 0xff) - else: - t = buf[0] >> 1 - return t - 0.25 + (buf[7] - buf[6]) / buf[7] - else: - t = buf[1] << 8 | buf[0] - if t & 0x8000: # sign bit set - t = -((t ^ 0xffff) + 1) - return t / 16 -- cgit v1.2.3