From 7aecefd053f032abd76e5456fe5caeda8104d9b8 Mon Sep 17 00:00:00 2001
From: Imbus <>
Date: Wed, 3 Apr 2024 17:47:08 +0200
Subject: [PATCH] Initial

---
 README.md | 15 +++++++++++++++
 blink.c   | 22 ++++++++++++++++++++++
 makefile  | 35 +++++++++++++++++++++++++++++++++++
 3 files changed, 72 insertions(+)
 create mode 100644 README.md
 create mode 100644 blink.c
 create mode 100644 makefile

diff --git a/README.md b/README.md
new file mode 100644
index 0000000..ddf093b
--- /dev/null
+++ b/README.md
@@ -0,0 +1,15 @@
+# STM32 Example
+
+This is unfinished work in progress.  
+The goal is to create a simple C example of a STM32F103C8T6 Blue Pill board running a simple program.
+
+`sudo dnf install arm-none-eabi-gcc-cs stlink`
+
+- [STM32F103C8T6 Blue Pill](https://stm32-base.org/boards/STM32F103C8T6-Blue-Pill.html)
+- [STM32F103C8T6 Blue Pill Datasheet](https://www.st.com/resource/en/datasheet/stm32f103c8.pdf)
+- [Bare Metal C on the Blue Pill](https://leap.tardate.com/arm/stm32f103c8t6/baremetal/)
+- [Bare Metal C on the Blue Pill Source Code](https://github.com/tardate/LittleArduinoProjects/tree/master/ARM/STM32F103C8T6/BareMetal)
+- [Bare Metal Embedded playlist](https://www.youtube.com/playlist?list=PLERTijJOmYrDiiWd10iRHY0VRHdJwUH4g)
+- [Getting Started With STM32](https://stm32-base.org/guides/getting-started)
+- [STM32-base source](https://github.com/STM32-base/STM32-base) and the specific [F1 Template](https://github.com/STM32-base/STM32-base-F1-template)
+- [stm32_bare_metal repository](https://github.com/mensi/stm32_bare_metal)
diff --git a/blink.c b/blink.c
new file mode 100644
index 0000000..06ee69d
--- /dev/null
+++ b/blink.c
@@ -0,0 +1,22 @@
+#include "stm32f103xb.h"
+
+#define LED_PIN GPIO_PIN_13
+#define LED_PORT GPIOC
+
+void delay(uint32_t count) {
+    for(uint32_t i = 0; i < count; i++);
+}
+
+int main(void) {
+    RCC->APB2ENR |= RCC_APB2ENR_IOPCEN; // Enable clock for GPIOC
+    GPIOC->CRH &= ~(GPIO_CRH_CNF13 | GPIO_CRH_MODE13); // Clear CNF and MODE bits for pin 13
+    GPIOC->CRH |= GPIO_CRH_MODE13_0; // Output mode, max speed 10 MHz
+
+    while (1) {
+        GPIOC->BSRR = LED_PIN; // Set pin high (turn LED on)
+        delay(1000000); // Delay
+        GPIOC->BSRR = LED_PIN << 16; // Reset pin (turn LED off)
+        delay(1000000); // Delay
+    }
+}
+
diff --git a/makefile b/makefile
new file mode 100644
index 0000000..fbfe41a
--- /dev/null
+++ b/makefile
@@ -0,0 +1,35 @@
+# Toolchain
+CC = arm-none-eabi-gcc
+OBJCOPY = arm-none-eabi-objcopy
+STFLASH = st-flash
+
+# Compiler flags
+CFLAGS = -std=c99 -Wall -Wextra -Werror -g -mthumb -mcpu=cortex-m3
+
+# Object files
+OBJS = blink.o
+
+# Output files
+ELF = blink.elf
+BIN = blink.bin
+
+# Targets
+.PHONY: all clean flash
+
+all: $(BIN)
+
+$(BIN): $(ELF)
+	$(OBJCOPY) -O binary $< $@
+
+$(ELF): $(OBJS)
+	$(CC) $(CFLAGS) $^ -o $@
+
+%.o: %.c
+	$(CC) $(CFLAGS) -c $< -o $@
+
+clean:
+	rm -f $(OBJS) $(ELF) $(BIN)
+
+flash: $(BIN)
+	$(STFLASH) --reset write $< 0x8000000
+