This week I got some inspiration from the ST DSP library, so I made my own oscilloscope with the STM32 and my 320x240 pixels QTFT screen. I made the code from scratch, both the sampling and screen updating code -- but I used the ST DSP library for the FFT calculations of course
You can see the video of the project here…
I have posted alot of projects recently, and here is another project with the Arduino!
This projects is about making a magnetic card lock using the Arduino, a servo and a $4 cheap magnetic card reader from AllElectronics.com
Magnetic Card Lock project
Magnetic Card Reader Connections
The card reader, which you can see in the first picture, has 7 pins. The picture below shows theese pins functionality!
I’ve made a video about the project which explains it all!
If you want to try it yourself, you can grab the code underneath and change the checkCode character array to match the string on your card!
#include <string.h> #include <Servo.h> Servo servo1; /* Magnetic Card lock with the Arduino and servo's * by Thomas Jespersen http://elec.tkjweb.dk * * Reads a magnetic stripe and opens lock (turns servo) if card is the same as programmed * */ // Connections: DATA = Pin 2, CLOCK = Pin 3, CARD IN = Pin 5 // See PDF "Magnetic Stripe Card Reader! << HACKMIAMI.pdf" for more connection information Read more...
Have you ever wondered if it was possible to overclock the STM32? It is, with a simple change in code line!
We only have to change the PLL setting, which is able to go up to 16 – so that means that we can overclock the STM32 up to 8MHz x 16 = 128 MHz
Here is the RCC Initialization code for 128MHz – remember, you also have to comment the “SYSCLK_FREQ_72MHz”, uncomment the “SYSCLK_FREQ_HSE” and set it to 128MHz in the system_stm32f10x.c
/*******************************************************************************
* Function Name : RCC_Configuration
* Description : Configures the different system clocks.
* Input : None
* Output : None
* Return : None
*******************************************************************************/
void RCC_Configuration(void)
{
/* RCC system reset(for debug purpose) */
RCC_DeInit();
/* Enable HSE */
RCC_HSEConfig(RCC_HSE_ON);
/* Wait till HSE is ready */
HSEStartUpStatus = RCC_WaitForHSEStartUp();
if(HSEStartUpStatus == SUCCESS)
{
/* Enable Prefetch Buffer */
FLASH_PrefetchBufferCmd(FLASH_PrefetchBuffer_Enable);
/* Flash 2 wait state */
FLASH_SetLatency(FLASH_Latency_2);
/* HCLK = SYSCLK */
RCC_HCLKConfig(RCC_SYSCLK_Div1);
/* PCLK2 = HCLK */
RCC_PCLK2Config(RCC_HCLK_Div1);
/* PCLK1 = HCLK/2 */
RCC_PCLK1Config(RCC_HCLK_Div2);
/* PLLCLK = 8MHz * 9 = 72 MHz */
//RCC_PLLConfig(RCC_PLLSource_HSE_Div1, RCC_PLLMul_9);
/* PLLCLK = 8MHz * 16 = 128 MHz */
RCC_PLLConfig(RCC_PLLSource_HSE_Div1, RCC_PLLMul_16);
// The frequency has also been changed in system_stm32f10x
/* Enable PLL */
RCC_PLLCmd(ENABLE);
/* Wait till PLL is ready */
while(RCC_GetFlagStatus(RCC_FLAG_PLLRDY) == RESET)
{;}
/* Select PLL as system clock source */
RCC_SYSCLKConfig(RCC_SYSCLKSource_PLLCLK);
/* Wait till PLL is used as system clock source */
while(RCC_GetSYSCLKSource() != 0x08)
{;}
}
/* Enable peripheral clocks --------------------------------------------------*/
/* Enable GPIOA, GPIOB, GPIOC, GPIOD, GPIOE, GPIOF, GPIOG and AFIO clocks */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_GPIOB |RCC_APB2Periph_GPIOC
| RCC_APB2Periph_GPIOD | RCC_APB2Periph_GPIOE | RCC_APB2Periph_GPIOF | RCC_APB2Periph_GPIOG
| RCC_APB2Periph_AFIO, ENABLE);
}
Here is the setup code to use the internal 8MHz clock – but with the internal clock, we are only able to get a max frequency of 36MHz.
void clock_init(){
/*Configure all clocks to max for best performance.
* If there are EMI, power, or noise problems, try slowing the clocks*/
/* First set the flash latency to work with our clock*/
/*000 Zero wait state, if 0 MHz < SYSCLK <= 24 MHz
001 One wait state, if 24 MHz < SYSCLK <= 48 MHz
010 Two wait states, if 48 MHz < SYSCLK <= 72 MHz */
FLASH_SetLatency(FLASH_Latency_1);
/* Start with HSI clock (internal 8mhz), divide by 2 and multiply by 9 to
* get maximum allowed frequency: 36Mhz
* Enable PLL, wait till it's stable, then select it as system clock*/
RCC_PLLConfig(RCC_PLLSource_HSI_Div2, RCC_PLLMul_9);
RCC_PLLCmd(ENABLE);
while(RCC_GetFlagStatus(RCC_FLAG_PLLRDY) == RESET) {}
RCC_SYSCLKConfig(RCC_SYSCLKSource_PLLCLK);
/* Set HCLK, PCLK1, and PCLK2 to SCLK (these are default */
RCC_HCLKConfig(RCC_SYSCLK_Div1);
RCC_PCLK1Config(RCC_HCLK_Div1);
RCC_PCLK2Config(RCC_HCLK_Div1);
/* Set ADC clk to 9MHz (14MHz max, 18MHz default)*/
RCC_ADCCLKConfig(RCC_PCLK2_Div4);
/*To save power, use below functions to stop the clock to ceratin
* peripherals
* RCC_AHBPeriphClockCmd
*/
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA, ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_ALL, ENABLE);
RCC_APB1PeriphClockCmd(RCC_APB1Periph_ALL, ENABLE);
}