init

.gitignore

@@ -0,0 +1,4 @@
+bin/
+*.elf
+*.bin
+generated.*.ld

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "libopencm3"]
+	path = libopencm3
+	url = https://github.com/libopencm3/libopencm3.git

.idea/.gitignore

@@ -0,0 +1,8 @@
+# Default ignored files
+/shelf/
+/workspace.xml
+# Datasource local storage ignored files
+/dataSources/
+/dataSources.local.xml
+# Editor-based HTTP Client requests
+/httpRequests/

.idea/misc.xml

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ExternalStorageConfigurationManager" enabled="true" />
+  <component name="MakefileSettings">
+    <option name="linkedExternalProjectsSettings">
+      <MakefileProjectSettings>
+        <option name="externalProjectPath" value="$PROJECT_DIR$" />
+        <option name="modules">
+          <set>
+            <option value="$PROJECT_DIR$" />
+          </set>
+        </option>
+        <option name="version" value="2" />
+      </MakefileProjectSettings>
+    </option>
+  </component>
+  <component name="MakefileWorkspace" PROJECT_DIR="$PROJECT_DIR$" />
+</project>

.idea/vcs.xml

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="$PROJECT_DIR$" vcs="Git" />
+    <mapping directory="$PROJECT_DIR$/libopencm3" vcs="Git" />
+  </component>
+</project>

Makefile

@@ -0,0 +1,22 @@
+V=1
+DEBUG=1
+PROJECT = dht_test
+BUILD_DIR = bin
+
+#SHARED_DIR = ../my-common-code
+CFILES = main.c
+#CFILES += api.c
+#AFILES += api-asm.S
+
+# TODO - you will need to edit these two lines!
+DEVICE=stm32f103rcbt6
+OOCD_FILE = board/stm32f4discovery.cfg
+
+# You shouldn't have to edit anything below here.
+#VPATH += $(SHARED_DIR)
+#INCLUDES += $(patsubst %,-I%, . $(SHARED_DIR))
+OPENCM3_DIR=libopencm3
+
+include $(OPENCM3_DIR)/mk/genlink-config.mk
+include rules.mk
+include $(OPENCM3_DIR)/mk/genlink-rules.mk

README.md

@@ -0,0 +1,7 @@
+## Build
+
+0. git submodule update --init (This is only needed once)
+1. make -C libopencm3 # (Only needed once)
+2. make
+
+

libopencm3

@@ -0,0 +1 @@
+Subproject commit 44928416eacb4c8d7774b1385c7f38fb226d080b

main.c

@@ -0,0 +1,156 @@
+/*
+ * This file is part of the libopencm3 project.
+ *
+ * Copyright (C) 2009 Uwe Hermann <uwe@hermann-uwe.de>
+ *
+ * This library is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this library.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <libopencm3/cm3/nvic.h>
+#include <libopencm3/stm32/rcc.h>
+#include <libopencm3/stm32/gpio.h>
+#include <libopencm3/stm32/timer.h>
+
+static void delay(int count)
+{
+	for (int i=0; i < count; i++) {
+		__asm__("nop");
+	}
+}
+
+static void gpio_setup(void)
+{
+	/* Enable GPIOA clock. */
+	/* Manually: */
+	// RCC_APB2ENR |= RCC_APB2ENR_IOPCEN;
+	/* Using API functions: */
+	rcc_periph_clock_enable(RCC_GPIOB);
+
+	/* Set GPIO5 (in GPIO port A) to 'output push-pull'. */
+	/* Manually: */
+	// GPIOA_CRH = (GPIO_CNF_OUTPUT_PUSHPULL << (((5 - 8) * 4) + 2));
+	// GPIOA_CRH |= (GPIO_MODE_OUTPUT_2_MHZ << ((5 - 8) * 4));
+	/* Using API functions: */
+	gpio_set_mode(GPIOB, GPIO_MODE_INPUT, GPIO_CNF_INPUT_PULL_UPDOWN, GPIO0);
+	gpio_set_mode(GPIOB, GPIO_MODE_OUTPUT_2_MHZ, GPIO_CNF_OUTPUT_PUSHPULL, GPIO1);
+	gpio_set_mode(GPIOB, GPIO_MODE_OUTPUT_2_MHZ, GPIO_CNF_OUTPUT_PUSHPULL, GPIO2);
+}
+
+static void tim_setup(void)
+{
+	nvic_enable_irq(NVIC_TIM3_IRQ);
+	nvic_set_priority(NVIC_TIM3_IRQ, 1);  // interupts will not work without it???
+
+	rcc_periph_clock_enable(RCC_TIM3);
+	rcc_periph_reset_pulse(RST_TIM3);
+
+	timer_set_mode(TIM3, TIM_CR1_CKD_CK_INT, TIM_CR1_CMS_EDGE, TIM_CR1_DIR_UP);
+	timer_set_prescaler(TIM3, 1152);  // set timer tickrate to 500khz
+	//timer_set_oc_value(TIM3, TIM_OC1, 0x1000);
+	timer_set_period(TIM3, 0xffff);
+	timer_one_shot_mode(TIM3);
+
+	timer_ic_set_input(TIM3, TIM_IC3, TIM_IC_IN_TI3);
+	//timer_ic_set_polarity(TIM3, TIM_IC3, TIM_IC_FALLING); // TIM_IC_RISING
+	//timer_ic_enable(TIM3, TIM_IC3);
+
+	timer_enable_counter(TIM3);
+	timer_enable_irq(TIM3, TIM_DIER_UIE);
+	timer_enable_irq(TIM3, TIM_DIER_CC1IE);  // end start condition
+	timer_enable_irq(TIM3, TIM_DIER_CC3IE);
+
+	// start condition
+	gpio_set_mode(GPIOB, GPIO_MODE_OUTPUT_2_MHZ, GPIO_CNF_OUTPUT_PUSHPULL, GPIO0);
+	gpio_clear(GPIOB, GPIO0);
+}
+
+enum DHT11_STATE {
+	DHT11_START,
+	DHT11_RESPONSE,
+	DHT11_BIT0,
+	DHT11_BIT1,
+	DHT11_END
+};
+
+int dht11_state = DHT11_START;
+
+void tim3_isr(void)
+{
+
+	if (timer_get_flag(TIM3, TIM_SR_UIF))  // timer reached end
+	{
+		timer_clear_flag(TIM3, TIM_SR_UIF);
+		//gpio_toggle(GPIOB, GPIO1);
+		gpio_toggle(GPIOB, GPIO2);
+
+		//timer_set_counter(TIM3, 0);
+		//timer_clear_flag(TIM3, TIM_SR_UIF);
+		//timer_set_oc_value(TIM3, TIM_OC1, 1000);
+	} else if (timer_get_flag(TIM3, TIM_SR_CC1IF))
+	{
+		timer_clear_flag(TIM3, TIM_SR_CC3IF);
+		if (dht11_state == DHT11_START){
+			gpio_set(GPIOB, GPIO0);
+			gpio_set_mode(GPIOB, GPIO_MODE_INPUT, GPIO_CNF_INPUT_PULL_UPDOWN, GPIO0);
+
+			// setup timer to wait for start response from dht11
+			timer_ic_set_polarity(TIM3, TIM_IC3, TIM_IC_FALLING); // TIM_IC_RISING
+			timer_ic_enable(TIM3, TIM_IC3);
+
+			dht11_state = DHT11_START;
+		}
+
+	} else if (timer_get_flag(TIM3, TIM_SR_CC3IF))  // PB0 changed value
+	{
+		timer_clear_flag(TIM3, TIM_SR_CC3IF);
+
+
+
+		if (timer_get_flag(TIM3, TIM_SR_CC3OF))
+		{
+			timer_clear_flag(TIM3, TIM_SR_CC3OF);
+		}
+	}
+
+}
+
+static void dht_start_signal(void)
+{
+	gpio_set_mode(GPIOB, GPIO_MODE_OUTPUT_2_MHZ, GPIO_CNF_OUTPUT_PUSHPULL, GPIO0);
+	gpio_clear(GPIOB, GPIO0);
+	delay(205000);
+	//delay(30000);
+	gpio_set(GPIOB, GPIO0);
+	delay(100);
+	gpio_set_mode(GPIOB, GPIO_MODE_INPUT, GPIO_CNF_INPUT_PULL_UPDOWN, GPIO0);
+}
+
+volatile int bla=0;
+
+int main(void)
+{
+	rcc_clock_setup_pll(&rcc_hse_configs[RCC_CLOCK_HSE8_72MHZ]);
+	gpio_setup();
+	tim_setup();
+
+	/* Blink the LED (PA5) on the board. */
+	while (1) {
+		/* Using API function gpio_toggle(): */
+		gpio_toggle(GPIOB, GPIO1);	/* LED on/off */
+		delay(4000000);
+		dht_start_signal();
+	}
+
+	return 0;
+}

openocd.cfg

@@ -0,0 +1,24 @@
+# This is an ST NUCLEO F103RB board with a single STM32F103RBT6 chip.
+# http://www.st.com/web/catalog/tools/FM116/SC959/SS1532/LN1847/PF259875
+
+interface ftdi
+transport select swd
+ftdi_vid_pid 0x0403 0x6010
+
+# ftdi_device_desc "USB Serial Converter A"
+# ftdi_device_desc "FT2232H ¿ª·¢°å"
+# ftdi_serial "FTZ7O8O0"
+
+ftdi_channel 1
+#adapter_khz 500
+#adapter_khz 8
+
+ftdi_layout_init 0x0018 0x05fb
+ftdi_layout_signal SWD_EN -data 0
+#ftdi_layout_signal nSRST -data 0x0020
+ftdi_layout_signal nTRST -ndata 0x0010 -noe 0x0040
+ftdi_layout_signal nSRST -ndata 0x0020 -noe 0x0040
+
+source [find target/stm32f1x.cfg]
+
+reset_config srst_only

rules.mk

@@ -0,0 +1,177 @@
+# This version of rules.mk expects the following to be defined before
+# inclusion..
+### REQUIRED ###
+# OPENCM3_DIR - duh
+# PROJECT - will be the basename of the output elf, eg usb-gadget0-stm32f4disco
+# CFILES - basenames only, eg main.c blah.c
+# CXXFILES - same for C++ files. Must have cxx suffix!
+# DEVICE - the full device name, eg stm32f405ret6
+#  _or_
+# LDSCRIPT - full path, eg ../../examples/stm32/f4/stm32f4-discovery/stm32f4-discovery.ld
+# OPENCM3_LIB - the basename, eg: opencm3_stm32f4
+# OPENCM3_DEFS - the target define eg: -DSTM32F4
+# ARCH_FLAGS - eg, -mthumb -mcpu=cortex-m4 -mfloat-abi=hard -mfpu=fpv4-sp-d16
+#    (ie, the full set of cpu arch flags, _none_ are defined in this file)
+#
+### OPTIONAL ###
+# INCLUDES - fully formed -I paths, if you want extra, eg -I../shared
+# BUILD_DIR - defaults to bin, should set this if you are building multiarch
+# OPT - full -O flag, defaults to -Os
+# CSTD - defaults -std=c99
+# CXXSTD - no default.
+# OOCD_INTERFACE - eg stlink-v2
+# OOCD_TARGET - eg stm32f4x
+#    both only used if you use the "make flash" target.
+# OOCD_FILE - eg my.openocd.cfg
+#    This overrides interface/target above, and is used as just -f FILE
+### TODO/FIXME/notes ###
+# No support for stylecheck.
+# No support for BMP/texane/random flash methods, no plans either
+# No support for magically finding the library.
+# C++ hasn't been actually tested with this..... sorry bout that. ;)
+# Second expansion/secondary not set, add this if you need them.
+
+BUILD_DIR ?= bin
+OPT ?= -Os
+CSTD ?= -std=c99
+
+# Be silent per default, but 'make V=1' will show all compiler calls.
+# If you're insane, V=99 will print out all sorts of things.
+V?=0
+ifeq ($(V),0)
+Q	:= @
+NULL	:= 2>/dev/null
+endif
+
+# Tool paths.
+PREFIX	?= arm-none-eabi-
+CC	= $(PREFIX)gcc
+CXX	= $(PREFIX)g++
+LD	= $(PREFIX)gcc
+OBJCOPY	= $(PREFIX)objcopy
+OBJDUMP	= $(PREFIX)objdump
+OOCD	?= openocd
+
+OPENCM3_INC = $(OPENCM3_DIR)/include
+
+# Inclusion of library header files
+INCLUDES += $(patsubst %,-I%, . $(OPENCM3_INC) )
+
+OBJS = $(CFILES:%.c=$(BUILD_DIR)/%.o)
+OBJS += $(CXXFILES:%.cxx=$(BUILD_DIR)/%.o)
+OBJS += $(AFILES:%.S=$(BUILD_DIR)/%.o)
+GENERATED_BINS = $(PROJECT).elf $(PROJECT).bin $(PROJECT).map $(PROJECT).list $(PROJECT).lss
+
+TGT_CPPFLAGS += -MD
+TGT_CPPFLAGS += -Wall -Wundef $(INCLUDES)
+TGT_CPPFLAGS += $(INCLUDES) $(OPENCM3_DEFS)
+
+TGT_CFLAGS += $(OPT) $(CSTD) -ggdb3
+TGT_CFLAGS += $(ARCH_FLAGS)
+TGT_CFLAGS += -fno-common
+TGT_CFLAGS += -ffunction-sections -fdata-sections
+TGT_CFLAGS += -Wextra -Wshadow -Wno-unused-variable -Wimplicit-function-declaration
+TGT_CFLAGS += -Wredundant-decls -Wstrict-prototypes -Wmissing-prototypes
+
+TGT_CXXFLAGS += $(OPT) $(CXXSTD) -ggdb3
+TGT_CXXFLAGS += $(ARCH_FLAGS)
+TGT_CXXFLAGS += -fno-common
+TGT_CXXFLAGS += -ffunction-sections -fdata-sections
+TGT_CXXFLAGS += -Wextra -Wshadow -Wredundant-decls  -Weffc++
+
+TGT_ASFLAGS += $(OPT) $(ARCH_FLAGS) -ggdb3
+
+TGT_LDFLAGS += -T$(LDSCRIPT) -L$(OPENCM3_DIR)/lib -nostartfiles
+TGT_LDFLAGS += $(ARCH_FLAGS)
+TGT_LDFLAGS += -specs=nano.specs
+TGT_LDFLAGS += -Wl,--gc-sections
+# OPTIONAL
+#TGT_LDFLAGS += -Wl,-Map=$(PROJECT).map
+ifeq ($(V),99)
+TGT_LDFLAGS += -Wl,--print-gc-sections
+endif
+
+# Linker script generator fills this in for us.
+ifeq (,$(DEVICE))
+LDLIBS += -l$(OPENCM3_LIB)
+endif
+# nosys is only in newer gcc-arm-embedded...
+#LDLIBS += -specs=nosys.specs
+LDLIBS += -Wl,--start-group -lc -lgcc -lnosys -Wl,--end-group
+
+# Burn in legacy hell fortran modula pascal yacc idontevenwat
+.SUFFIXES:
+.SUFFIXES: .c .S .h .o .cxx .elf .bin .list .lss
+
+# Bad make, never *ever* try to get a file out of source control by yourself.
+%: %,v
+%: RCS/%,v
+%: RCS/%
+%: s.%
+%: SCCS/s.%
+
+all: $(PROJECT).elf $(PROJECT).bin
+flash: $(PROJECT).flash
+
+# error if not using linker script generator
+ifeq (,$(DEVICE))
+$(LDSCRIPT):
+ifeq (,$(wildcard $(LDSCRIPT)))
+    $(error Unable to find specified linker script: $(LDSCRIPT))
+endif
+else
+# if linker script generator was used, make sure it's cleaned.
+GENERATED_BINS += $(LDSCRIPT)
+endif
+
+# Need a special rule to have a bin dir
+$(BUILD_DIR)/%.o: %.c
+	@printf "  CC\t$<\n"
+	@mkdir -p $(dir $@)
+	$(Q)$(CC) $(TGT_CFLAGS) $(CFLAGS) $(TGT_CPPFLAGS) $(CPPFLAGS) -o $@ -c $<
+
+$(BUILD_DIR)/%.o: %.cxx
+	@printf "  CXX\t$<\n"
+	@mkdir -p $(dir $@)
+	$(Q)$(CXX) $(TGT_CXXFLAGS) $(CXXFLAGS) $(TGT_CPPFLAGS) $(CPPFLAGS) -o $@ -c $<
+
+$(BUILD_DIR)/%.o: %.S
+	@printf "  AS\t$<\n"
+	@mkdir -p $(dir $@)
+	$(Q)$(CC) $(TGT_ASFLAGS) $(ASFLAGS) $(TGT_CPPFLAGS) $(CPPFLAGS) -o $@ -c $<
+
+$(PROJECT).elf: $(OBJS) $(LDSCRIPT) $(LIBDEPS)
+	@printf "  LD\t$@\n"
+	$(Q)$(LD) $(TGT_LDFLAGS) $(LDFLAGS) $(OBJS) $(LDLIBS) -o $@
+
+%.bin: %.elf
+	@printf "  OBJCOPY\t$@\n"
+	$(Q)$(OBJCOPY) -O binary  $< $@
+
+%.lss: %.elf
+	$(OBJDUMP) -h -S $< > $@
+
+%.list: %.elf
+	$(OBJDUMP) -S $< > $@
+
+%.flash: %.elf
+	@printf "  FLASH\t$<\n"
+ifeq (,$(OOCD_FILE))
+	$(Q)(echo "halt; program $(realpath $(*).elf) verify reset" | nc -4 localhost 4444 2>/dev/null) || \
+		$(OOCD) -f interface/$(OOCD_INTERFACE).cfg \
+		-f target/$(OOCD_TARGET).cfg \
+		-c "program $(realpath $(*).elf) verify reset exit" \
+		$(NULL)
+else
+	$(Q)(echo "halt; program $(realpath $(*).elf) verify reset" | nc -4 localhost 4444 2>/dev/null) || \
+		$(OOCD) -f $(OOCD_FILE) \
+		-c "program $(realpath $(*).elf) verify reset exit" \
+		$(NULL)
+endif
+
+clean:
+	rm -rf $(BUILD_DIR) $(GENERATED_BINS)
+
+.PHONY: all clean flash
+-include $(OBJS:.o=.d)
+