Files and notes for the "STM32 for Arduino Users" workshop at HackerHotel 2020
This workshop is intended for people who are annoyed of the chains Arduino and other electronics beginners ecosystems like MicroPhython or low.js has put on them. We would like to show you how to use industrie's standard frameworks and toolchains to program high-performance ARM-based microcontrollers. Most of the tools used are open source and all are free to use, so they can easily be integrated in everydays hacking projects.
This workshop is intended for people who already are familiar with low-level programming, idealy something C / C++-based like Arduino. This workshop is not an introduction to electronics, nor programming. All tools used require Linux, so either bring your Linux laptop, or have a VM at hands that has USB hardware access.
Schedule:
- Introduction to STM32 microcontroller families
- Hardware Peripherals vs. Software BitBanging
- Introduction to CubeMX, a code generation tool for STM32 hardware init
- Setting up the compiler and flash tool
- Blinking a LED
- Introduction to DMA and advanced hardware peripherals
- Displaying stuff on a 8x8 LED matrix with zero CPU overhead
- Introduction to the GNU Project Debugger for STM32
- Experimenting and Questions
You will receive all hardware required for participating for a cost of 15โฌ. Unfortuantly, we can only provide 10 kits consisting of an OtterPill STM32F072 based STM32 devboard, a ST-Link V2 USB debugger and a MAX7219 LED Matrix. If you did not get a kit, you can also participate as a listener or bring your own related hardware.
If you would like to join, please prepare the following software on your laptop:
sudo apt-get update
sudo apt-get install openocd gcc-arm-none-eabi cmake build-essential libusb-1.0-0-dev openjdk-13-jre dfu-util stlink-tools
(evt. sudo apt install libc6-i386 libnewlib-arm-none-eabi)
If you don't have stlink-tools, compile from scratch:
https://github.com/texane/stlink
https://github.com/texane/stlink/blob/master/doc/compiling.md
If you have arm-none-eabi-gcc V6 (check with 'arm-none-eabi-gcc - v'):
sudo add-apt-repository ppa:team-gcc-arm-embedded/ppa
sudo apt-get update
sudo apt-get install gcc-arm-embedded
https://www.st.com/en/development-tools/stm32cubemx.html
extract, launch with
java -jar STM32CubeMX
e.g. Atom, Sublime, vscode
https://github.com/Jan--Henrik/hackerhotel-stm-workshop
https://github.com/Jan--Henrik/OtterPill
CubeMX, file -> New Project
Select STM32F072C8Tx, LQFP48
(left)
System Core -> SYS -> Debug Serial Wire
PB13 -> GPIO Output
PB13 -> right-click -> Enter user label -> "LED"
(top)
Project Manager
select name
select location
Toolchain / IDE -> Makefile
(top right)
Generate Code
Open Terminal, locate to project location
Launch editor in project root directory
make
Should compile just fine
Src -> main.c (https://github.com/Jan--Henrik/hackerhotel-stm-workshop/blob/master/blink/Src/main.c)
add line 100:
HAL_GPIO_WritePin(LED_GPIO_Port, LED_Pin, 1);
HAL_Delay(100);
HAL_GPIO_WritePin(LED_GPIO_Port, LED_Pin, 0);
HAL_Delay(100);
In console type
make
Should compile just fine
plug in the OtterPill while pressing the DFU button
lsusb
should show something like:
Bus 001 Device 007: ID 0483:df11 STMicroelectronics STM Device in DFU Mode
flash with dfu-util:
dfu-util -a 0 -s 0x08000000:leave -D build/blink.bin
(left)
System Core -> SYS -> Debug Serial Wire
Timers -> TIM1 -> Channel 1: PWM Generation CH1N or PB13 -> TIM1_CH1N
Parameter Settings -> Counter Settings -> Prescaler -> 2000
Parameter Settings -> Counter Settings -> Counter Periode -> 99
Parameter Settings -> PWM Generation Channel 1N -> Pulse -> 50
NVIC Settings -> TIM1 break, update... interrupts -> enable
Connectivity -> SPI1 -> Mode: Full-Dublex Master
Connectivity -> SPI1 -> : Hardware NSS Signal: Hardware NSS Signal Output
Parameter Settings -> Data Size -> 16
Parameter Settings -> Clock Parameter -> Prescaler -> 8
DMA Settings -> Add -> SPI1_TX
(top)
Clock Configuration -> System Clock MUX, select HSI48
(top)
Project Manager
select name
select location
Toolchain / IDE -> Makefile
(top right)
Generate Code
Open Terminal, locate to project location
Launch editor in project root directory
make
Should compile just fine
Src -> main.c (https://github.com/Jan--Henrik/hackerhotel-stm-workshop/blob/master/matrix-test-monochrome/Src/main.c)
add line 40 (/* USER CODE BEGIN PM */):
void setPixel(uint8_t x, uint8_t y, uint8_t c);
add line 50 (/* USER CODE BEGIN PV */):
uint16_t fbuf[8];
uint16_t cbuf[5]={0x0b07, //scanLimit no limit
0x0900, //decode mode none
0x0c01, //shutdown off
0x0f00, //display test off
0x0a0f}; //intensity max
int16_t color;
uint64_t lastTick;
uint32_t tickTime;
add line 109 (/* USER CODE BEGIN 2 */):
HAL_SPI_Init(&hspi1);
HAL_SPI_Transmit_DMA(&hspi1,cbuf,5);
for(uint8_t i = 1; i <= 8; i++){
fbuf[i-1] = (i << 8);
//fbuf[i-1] = fbuf[i-1] + 0xF5;
}
HAL_TIM_Base_Start_IT(&htim1);
HAL_TIMEx_PWMN_Start(&htim1,TIM_CHANNEL_1);
add line 129:
lastTick = HAL_GetTick();
for(uint8_t x = 0; x <= 7; x++){
for(uint8_t y = 0; y <= 7; y++){
color = 127.0 + sin((10.0*(((x-4)/8.0)*sin(HAL_GetTick()/500.0)+((y-4)/8.0)*cos(HAL_GetTick()/300.0)))+HAL_GetTick()/10000.0);
setPixel(x,y,color > 126 ? 1:0);
}
}
tickTime = HAL_GetTick() - lastTick;
HAL_SPI_Transmit_DMA(&hspi1,fbuf,8);
add line 314:
void setPixel(uint8_t x, uint8_t y, uint8_t c){
if(x > 7 || y > 7) return;
c = c & 0x01;
fbuf[y] ^= (-c ^ fbuf[y]) & (1UL << x);
}
In console type
make
Should compile just fine
Wire up your led matrix:
plug in the OtterPill while pressing the DFU button
lsusb
should show something like:
Bus 001 Device 007: ID 0483:df11 STMicroelectronics STM Device in DFU Mode
flash with dfu-util:
dfu-util -a 0 -s 0x08000000:leave -D build/matrix-test-monochrome.bin
(left)
System Core -> SYS -> Debug Serial Wire
Timers -> TIM1 -> Channel 1: PWM Generation CH1N or PB13 -> TIM1_CH1N
Parameter Settings -> Counter Settings -> Prescaler -> 2000
Parameter Settings -> Counter Settings -> Counter Periode -> 99
Parameter Settings -> PWM Generation Channel 1N -> Pulse -> 50
NVIC Settings -> TIM1 break, update... interrupts -> enable
Connectivity -> SPI1 -> Mode: Full-Dublex Master
Connectivity -> SPI1 -> : Hardware NSS Signal: Hardware NSS Signal Output
Parameter Settings -> Data Size -> 16
Parameter Settings -> Clock Parameter -> Prescaler -> 8
DMA Settings -> Add -> SPI1_TX ->
(top)
Clock Configuration -> System Clock MUX, select HSI48
(top)
Project Manager
select name
select location
Toolchain / IDE -> Makefile
top right: Generate Code
Open Terminal, locate to project location
Launch editor in project root directory
Launch console and type
make
Should compile just fine
Src -> main.c (https://github.com/Jan--Henrik/hackerhotel-stm-workshop/blob/master/matrix-test-grayscale/Src/main.c)
add line 30 (/* USER CODE BEGIN PTD */):
#define FBDEPH 4
#define FBDEPHPOW 16
add line 49 (/* USER CODE BEGIN PV */)
uint8_t modCnt = 0;
uint16_t fbuf[FBDEPH][8];
uint16_t cbuf[5]={0x0b07, //scanLimit no limit
0x0900, //decode mode none
0x0c01, //shutdown off
0x0f00, //display test off
0x0a0f}; //intensity max
int16_t color;
uint64_t lastTick;
uint32_t tickTime;
add line 69 (/* USER CODE BEGIN PM */):
void setPixel(uint8_t x, uint8_t y, uint8_t c);
add line 111 (/* USER CODE BEGIN 2 */):
HAL_SPI_Init(&hspi1);
HAL_SPI_Transmit_DMA(&hspi1,cbuf,4);
for(uint8_t i = 1; i <= 8; i++){
for(uint8_t j = 0; j <= FBDEPH-1; j++){
fbuf[j][i-1] = (i << 8);
}
}
HAL_TIM_Base_Start_IT(&htim1);
HAL_TIMEx_PWMN_Start(&htim1,TIM_CHANNEL_1);
add line 131:
lastTick = HAL_GetTick();
for(uint8_t x = 0; x <= 7; x++){
for(uint8_t y = 0; y <= 7; y++){
color = 32.0 + sin((10.0*(((x-4)/8.0)*sin(HAL_GetTick()/500.0)+((y-4)/8.0)*cos(HAL_GetTick()/300.0)))+HAL_GetTick()/10000.0)*32;
//color = x*64;
setPixel(x,y,color);
}
}
tickTime = HAL_GetTick() - lastTick;
add line 342 (/* USER CODE BEGIN 4 */):
void setPixel(uint8_t x, uint8_t y, int16_t c){
if(x > 7 || y > 7) return;
if(c >= FBDEPHPOW) c = FBDEPHPOW-1;
if(c < 0) c = 0;
//c = c & 0x01;
uint8_t cBit;
for(uint8_t i = 0; i <= FBDEPH-1; i++){
cBit = c & 0x01;
fbuf[i][y] ^= (-cBit ^ fbuf[i][y]) & (1UL << x);
c = c >> 1;
}
}
Src -> stm32f0xx_it.c (https://github.com/Jan--Henrik/hackerhotel-stm-workshop/blob/master/matrix-test-grayscale/Src/stm32f0xx_it.c)
add line 35:
#define FBDEPH 4
#define FBDEPHPOW 16
add line 64:
extern uint16_t fbuf[8][8];
extern uint8_t modCnt;
add in "void TIM1_BRK_UP_TRG_COM_IRQHandler(void)"
if(__HAL_TIM_GET_FLAG(&htim1,TIM_FLAG_UPDATE) && HAL_DMA_GetState(&hdma_spi1_tx) == HAL_DMA_STATE_READY){
modCnt++;
modCnt = modCnt % FBDEPH;
__HAL_TIM_SET_PRESCALER(&htim1,(((modCnt+FBDEPH+1)%FBDEPH)*100));
__HAL_TIM_SET_COUNTER(&htim1,0);
HAL_SPI_Transmit_DMA(&hspi1,&fbuf[modCnt][0],8);
}
In console type
make
Should compile just fine
wire up your led matrix:
plug in the OtterPill while pressing the DFU button
lsusb
should show something like:
Bus 001 Device 007: ID 0483:df11 STMicroelectronics STM Device in DFU Mode
flash with dfu-util:
dfu-util -a 0 -s 0x08000000:leave -D build/matrix-test-monochrome.bin
st-flash write build/workshop-debug-test.bin 0x8000000
st-utils
Start GDB client
arm-none-eabi-gdb build/matrix-test-monochrome.elf --tui
Connect to target and run code
target extended-remote :4242
continue
Set breakpoint at main
b main
Reload and flash bin
load build/workshop-debug-test.elf
Print variable
p $var
Set breakpoint at line 132 (in main.c) and print variable everytime the breakpoint is reached
break 132
commands
silent
p $var
cont
end