micropython: add micropython component

components/language/micropython/drivers/dht/dht.c

@@ -0,0 +1,94 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2016 Damien P. George
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include <stdio.h>
+
+#include "py/runtime.h"
+#include "py/mperrno.h"
+#include "py/mphal.h"
+#include "extmod/machine_pulse.h"
+#include "drivers/dht/dht.h"
+
+// Allow the open-drain-high call to be DHT specific for ports that need it
+#ifndef mp_hal_pin_od_high_dht
+#define mp_hal_pin_od_high_dht mp_hal_pin_od_high
+#endif
+
+STATIC mp_obj_t dht_readinto(mp_obj_t pin_in, mp_obj_t buf_in) {
+    mp_hal_pin_obj_t pin = mp_hal_get_pin_obj(pin_in);
+    mp_hal_pin_open_drain(pin);
+
+    mp_buffer_info_t bufinfo;
+    mp_get_buffer_raise(buf_in, &bufinfo, MP_BUFFER_WRITE);
+
+    if (bufinfo.len < 5) {
+        mp_raise_ValueError(MP_ERROR_TEXT("buffer too small"));
+    }
+
+    // issue start command
+    mp_hal_pin_od_high_dht(pin);
+    mp_hal_delay_ms(250);
+    mp_hal_pin_od_low(pin);
+    mp_hal_delay_ms(18);
+
+    mp_uint_t irq_state = mp_hal_quiet_timing_enter();
+
+    // release the line so the device can respond
+    mp_hal_pin_od_high_dht(pin);
+    mp_hal_delay_us_fast(10);
+
+    // wait for device to respond
+    mp_uint_t ticks = mp_hal_ticks_us();
+    while (mp_hal_pin_read(pin) != 0) {
+        if ((mp_uint_t)(mp_hal_ticks_us() - ticks) > 100) {
+            goto timeout;
+        }
+    }
+
+    // time pulse, should be 80us
+    ticks = machine_time_pulse_us(pin, 1, 150);
+    if ((mp_int_t)ticks < 0) {
+        goto timeout;
+    }
+
+    // time 40 pulses for data (either 26us or 70us)
+    uint8_t *buf = bufinfo.buf;
+    for (int i = 0; i < 40; ++i) {
+        ticks = machine_time_pulse_us(pin, 1, 100);
+        if ((mp_int_t)ticks < 0) {
+            goto timeout;
+        }
+        buf[i / 8] = (buf[i / 8] << 1) | (ticks > 48);
+    }
+
+    mp_hal_quiet_timing_exit(irq_state);
+    return mp_const_none;
+
+timeout:
+    mp_hal_quiet_timing_exit(irq_state);
+    mp_raise_OSError(MP_ETIMEDOUT);
+}
+MP_DEFINE_CONST_FUN_OBJ_2(dht_readinto_obj, dht_readinto);

components/language/micropython/drivers/dht/dht.h

@@ -0,0 +1,8 @@
+#ifndef MICROPY_INCLUDED_DRIVERS_DHT_DHT_H
+#define MICROPY_INCLUDED_DRIVERS_DHT_DHT_H
+
+#include "py/obj.h"
+
+MP_DECLARE_CONST_FUN_OBJ_2(dht_readinto_obj);
+
+#endif // MICROPY_INCLUDED_DRIVERS_DHT_DHT_H

components/language/micropython/drivers/dht/dht.py

@@ -0,0 +1,46 @@
+# DHT11/DHT22 driver for MicroPython on ESP8266
+# MIT license; Copyright (c) 2016 Damien P. George
+
+import sys
+
+if sys.platform.startswith("esp"):
+    from esp import dht_readinto
+elif sys.platform == "mimxrt":
+    from mimxrt import dht_readinto
+elif sys.platform == "rp2":
+    from rp2 import dht_readinto
+elif sys.platform == "pyboard":
+    from pyb import dht_readinto
+else:
+    from machine import dht_readinto
+
+
+class DHTBase:
+    def __init__(self, pin):
+        self.pin = pin
+        self.buf = bytearray(5)
+
+    def measure(self):
+        buf = self.buf
+        dht_readinto(self.pin, buf)
+        if (buf[0] + buf[1] + buf[2] + buf[3]) & 0xFF != buf[4]:
+            raise Exception("checksum error")
+
+
+class DHT11(DHTBase):
+    def humidity(self):
+        return self.buf[0]
+
+    def temperature(self):
+        return self.buf[2]
+
+
+class DHT22(DHTBase):
+    def humidity(self):
+        return (self.buf[0] << 8 | self.buf[1]) * 0.1
+
+    def temperature(self):
+        t = ((self.buf[2] & 0x7F) << 8 | self.buf[3]) * 0.1
+        if self.buf[2] & 0x80:
+            t = -t
+        return t