add support for weighing sensor HX710/HX711

klippy/extras/hx71x.py

@@ -0,0 +1,88 @@
+# HX710/HX711 weighing sensor support
+#
+# Copyright (C) 2023 guoge <[email protected]>
+#
+# This file may be distributed under the terms of the GNU GPLv3 license.
+import logging
+import mcu
+
+######################################################################
+# Compatible Sensors:
+#       HX710A / HX711 / HX712
+######################################################################
+
+
+class HX71X:
+    def __init__(self, config):
+        self.printer = config.get_printer()
+        self.name = config.get_name().split()[-1]
+        self.reactor = self.printer.get_reactor()
+        self.mcu = mcu.get_printer_mcu(self.printer,
+                                       config.get('hx71x_mcu', 'mcu'))
+        self.oid = self.mcu.create_oid()
+
+        # Determine pin from config
+        ppins = config.get_printer().lookup_object("pins")
+        sck_params = ppins.lookup_pin(config.get('hx71x_sck_pin'))
+        dout_params = ppins.lookup_pin(config.get('hx71x_dout_pin'))
+
+        self.mcu.add_config_cmd(
+            "config_hx71x oid=%d  sck_pin=%s dout_pin=%s"
+            % (self.oid, sck_params['pin'], dout_params['pin']))
+
+        #update period
+        self.report_time = config.getfloat('hx71x_report_time', 2, 
+                                           minval=0.02)
+
+        #unit scale
+        self.scale = config.getfloat('hx71x_scale', 0.001)
+
+        self.weight = 0.0
+        self.sample_timer = self.reactor.register_timer(self._sample_hx71x)
+        self.printer.add_object("hx71x " + self.name, self)
+        self.printer.register_event_handler("klippy:connect", 
+                                            self.handle_connect)
+
+        self.cmd_queue = self.mcu.alloc_command_queue()
+        self.mcu.register_config_callback(self.build_config)
+
+    def handle_connect(self):
+        self.reactor.update_timer(self.sample_timer, self.reactor.NOW)
+        return
+
+    def build_config(self):
+        self.read_hx71x_cmd = self.mcu.lookup_query_command(
+            "read_hx71x oid=%c read_len=%u",
+            "read_hx71x_response oid=%c response=%*s", oid=self.oid,
+            cq=self.cmd_queue)
+
+    def read_hx71x(self, read_len):
+        return self.read_hx71x_cmd.send([self.oid, read_len])
+
+    def setup_callback(self, cb):
+        self._callback = cb
+
+    def get_report_time_delta(self):
+        return self.report_time
+
+    def _sample_hx71x(self, eventtime):
+        params = self.read_hx71x(4)
+
+        response = bytearray(params['response'])
+        w = int.from_bytes(response, byteorder='little', signed=True)
+        self.weight = w * self.scale # weight scale
+
+        logging.info(" read hx711 @ %.3f , weight:%.2f", eventtime, self.weight)
+        return eventtime + self.report_time
+
+    def get_status(self, eventtime):
+        return {
+            'weight': round(self.weight, 2)
+        }
+
+
+def load_config(config):
+    return HX71X(config)
+
+def load_config_prefix(config):
+    return HX71X(config)

src/Makefile

@@ -1,6 +1,6 @@
 # Main code build rules
 
-src-y += sched.c command.c basecmd.c debugcmds.c
+src-y += sched.c command.c basecmd.c debugcmds.c hx71x.c
 src-$(CONFIG_HAVE_GPIO) += initial_pins.c gpiocmds.c stepper.c endstop.c \
     trsync.c
 src-$(CONFIG_HAVE_GPIO_ADC) += adccmds.c

src/hx71x.c

@@ -0,0 +1,141 @@
+// Commands for read weight from HX710A/HX711/HX712.
+//
+// Copyright (C) 2023  guoge <[email protected]>
+//
+// This file may be distributed under the terms of the GNU GPLv3 license.
+
+#include <string.h> // memcpy
+#include "autoconf.h" //
+#include "basecmd.h" //oid_alloc
+#include "command.h"  //sendf
+#include "sched.h" //DECL_COMMAND
+#include "board/gpio.h" //GPIO/read/setup
+#include "generic/armcm_timer.h" // udelay
+
+
+struct hx71x_s {
+    struct gpio_out sck_out;
+    struct gpio_in dt_in;
+    long weight_tare;
+    long pulse_count;
+};
+
+long HX711_Read(struct hx71x_s *dev);
+void HX711_Get_WeightTare(struct hx71x_s *dev);
+long HX711_Get_Weight(struct hx71x_s *dev);
+
+
+void command_config_hx71x(uint32_t *args)
+{
+    struct hx71x_s *hx71x = oid_alloc(args[0], command_config_hx71x
+                                     , sizeof(*hx71x));
+    hx71x->sck_out = gpio_out_setup(args[1], 1);
+    hx71x->dt_in = gpio_in_setup(args[2], 1);
+    gpio_out_write(hx71x->sck_out, 0);
+
+    hx71x->weight_tare = 0;
+}
+DECL_COMMAND(command_config_hx71x, 
+    "config_hx71x oid=%c sck_pin=%u dout_pin=%u");
+
+
+struct hx71x_s * hx71x_oid_lookup(uint8_t oid)
+{
+    return oid_lookup(oid, command_config_hx71x);
+}
+
+
+void command_read_hx71x(uint32_t * args)
+{
+    static int s_nCnt = 0;
+    s_nCnt++;
+
+    uint8_t oid = args[0];
+    struct hx71x_s *dev = hx71x_oid_lookup(args[0]);
+    dev->pulse_count = args[1];
+    uint8_t data_len = 4;
+    uint8_t data[data_len];
+
+    long weight = HX711_Get_Weight(dev);
+    data[0] = weight & 0xFF;
+    data[1] = (weight>>8) & 0xFF;
+    data[2] = (weight>>16) & 0xFF;
+    data[3] = (weight>>24) & 0xFF;
+    sendf("read_hx71x_response oid=%c response=%*s", oid, data_len, data);
+}
+DECL_COMMAND(command_read_hx71x, "read_hx71x oid=%c read_len=%u");
+
+
+//read data form HX711
+long HX711_Read(struct hx71x_s *dev)
+{
+    //gpio_out_reset(dev->sck_out, 0);
+    gpio_out_write(dev->sck_out, 0);
+    udelay(1);
+
+    //wait dout to low.
+    //gpio_in_reset(dev->dt_in, 1);
+    int nCnt = 0;
+    while ( gpio_in_read(dev->dt_in) )
+    {
+        udelay(1);
+        if (nCnt++> 100 * 1000)
+            return 0;
+    }
+
+    //read 24bit data.
+    unsigned long count=0;
+    for (int i = 0; i < 24; i++)
+    {
+        gpio_out_write(dev->sck_out, 1);
+        udelay(1);
+
+        count = count << 1;
+
+        gpio_out_write(dev->sck_out, 0);
+        udelay(1);
+
+        if( gpio_in_read(dev->dt_in) )
+            count++;
+    } 
+
+    //last clk, total 25/26/27
+    int n = 1;
+    if( dev->pulse_count==26 )
+        n = 2;
+    else if( dev->pulse_count==27 )
+        n = 3;
+
+    for (int i = 0; i < n; i++)
+    {
+        gpio_out_write(dev->sck_out, 1);
+        udelay(1);
+        gpio_out_write(dev->sck_out, 0);
+        udelay(1);
+    }
+
+    count ^= 0x800000;
+    return count;
+}
+
+//set weight tare.
+void HX711_Get_WeightTare(struct hx71x_s* dev)
+{
+    dev->weight_tare = HX711_Read(dev);
+}
+
+//get weight
+long HX711_Get_Weight(struct hx71x_s* dev)
+{
+    static int s_nCnt = 0;
+
+    long value = HX711_Read(dev);
+
+    if( s_nCnt<2 ) //reset weight tare at 1/2 times.
+    {
+        s_nCnt++;
+        dev->weight_tare = value;
+    }
+
+    return value - dev->weight_tare;
+}