spi pwm

This article introduces a program of 51 series single-chip microcomputer that uses pulse width modulation (PWM) to control the brightness of LED lights. We all know that 51 Single-Chip Microcomputer itself has no pwm interface. This program is The software simulates pwm and adjusts the duty cycle of high voltage and low level in a certain frequency square wave to

Discussion on the understanding of PWM1. What is PWM?PWM (pulse width modulation) is a simple frequency conversion technology, is to change the pulse width to control the output voltage, by changing the period to control its output frequency. If it's not clear enough, well, let's take a look at the examples in our real life, why do we have to twist the fan, the speed of the fan will change; adjust the sound

PWM is a technology to regulate the output power (commonly known as voltage regulation), the principle is to change the duty ratio of the output square wave, the specific output see: The output signal is the voltage value, when the load is constant resistance, the output power is 25%, 50%, 75%, respectively. The implementation method is as follows: Set up a counter in which the first line is a 4-bit counter that automatically changes to 0 p

Differences: SPI: high-speed synchronous serial port. 3 ~ 4-line interface, independent and synchronous sending and receiving UART: Universal asynchronous serial port. Bidirectional communication based on the standard baud rate is slow I2C: A three-line serial transmission mode. The communication protocol and usage can be found on the Internet. Bidirectional data transmission with three linesSerial peripheral interfaceUART: Universal asynchronous tra

From the following address: http://www.byteparadigm.com/applications/introduction-to-i2c-and-spi-protocols/I²c vs SPIToday, at the low end of the communication protocols, we find i²c (for ' inter-integrated Circuit ', Protocol) and SPI (for ' Serial peripheral Interface '). Both protocols is well-suited for communications between integrated circuits, for slow communication with on-board PERIPH Erals. At the

Now that we know the protocol, we can start to look at the SPI driver code in Linux kenerl. There are many struct in the code, so let's take a look at the main struct first, in this way, we can better understand the driver. Mainly include/Linux/SPI. h The first is the communication interface between the SPI host and the slave, that is, the

STM32 advanced timer TIM1 generates two-way complementary PWM wave (with dead zone), stm32tim1 Test environment: Keil 5.2.160.0 STM32F103RBT6 Firmware Library version: STM32F10x_StdPeriph_Lib_V3.5.0 (2011) In this paper, TIM1 Channel 1 and Channel 2 are used to generate two complementary PWM waves with 1 khz and 1 us dead zone. IO port used: We use pin PA9, PA10, complementary Output Using PB14, PB15 Some

Stm32f103zet6 in a total of 8 timers, including advanced Timers TIM1-TIM5, TIM8, a total of 6. There is a need to use the CASCADE function of the timer, the ST's RM0008 REV12 P388 and P399 page is explained for the specific timer, how to choose the Cascade function, see table 86. Here I output PWM timer is TIM2, idle timer is TIM3. With TIM2 as the main timer, TIM3 counts the number of output pulses from the timer to TIM2. Check table shows that TIM3

OID Tim3_init (void){Tim_timebaseinittypedef tim_timebasestructure;Tim_ocinittypedef tim_ocinitstructure;/* PWM signal level hopping value */U16 ccr1= 36000;U16 Ccr2= 36000;/*pclk1 after twice octave as TIM3 clock source equals 72mhz*/Rcc_apb1periphclockcmd (RCC_APB1PERIPH_TIM3, ENABLE);/* Time Base configuration */Tim_timebasestructure.tim_period = 1599; Counting Cycle 1600Tim_timebasestructure.tim_prescaler = 1; Set Prescaler: Prescaler = 2, which i

#include //program is written based on KEIL-C51, introducing 8051 header files Sbit p10=p1^0; Sbit p11=p1^1;unsigned intScale//Duty ratio control variablevoidMainvoid) {unsigned intN//delay cycle variableTmod=0x02;//Timer 0, operating mode 2 (0000 0010), 8-bit timingth0=0x06;//Timing 250US (12M oscillator)tl0=0x06;//Preset valuetr0=1;//Start timer 0et0=1;//Start Timer 0 InterruptEa=1;//Open Total Interrupt while(1) { for(n=0;n50000; n++);//delay for some timescale++;//Duty ratio cont

1, first set up software simulation, you can see the STM32 not complete manual of the 2.4 software simulation chapter(Original file name: 1.jpg)Example functionality:-Clock Settings:-XTAL = 8.00 MHz-SYSCLK = 72.00 MHz-HCLK = SYSCLK = 72.00 MHz-PCLK1 = HCLK/2 = 36.00 MHz-PCLK2 = HCLK = 72.00 MHz-ADCLK = PCLK2/6 = 12.00 MHz-SYSTICK = HCLK/8 = 9.00 MHz-TIM4 is running at 100Hz.LEDs PB8, PB9 is dimmed using the PWM function of TIM4 channel3, Channel4The T

2015.4.8Sunny WednesdayWhat the teacher said today is the kernel to write led and PWM driver, to achieve the function of pattern lights and singing. Understand the application and the driver of the docking, and finally realized in the song at the time according toThe rhythm of the song Lights out a small lamp, should be two independent drivers have been written, want to combine is actually very simple, as long as in the master function inside open two

, 3, change the armature circuit resistance. The use of single-chip microcomputer to control the speed of the DC motor, the general use of the method of regulating the armature voltage, through a single-chip microcomputer control pwm1,pwm2, to produce a variable pulse, so that the voltage on the motor is also a variable width pulse voltage. According to the formula U=avcc Wherein: U is the armature voltage, A is the pulse duty ratio (0 The armature voltage of the motor is controlled by the outp

Purpose of study: (1) familiar with SPI interface and its read-write timing;(2) Review the $READMEMB command and $display command in the Verilog simulation statement;(3) Mastering the SPI Interface write sequential operation of the hardware language description process (in this case only write timing for example), for the later description of more complex sequential logic circuit lay the foundation.Learning

MSM8909 + Android5.1.1 SPI driver development (PSAM part) MSM8909 + Android5.1.1SPI driver development (PSAM part) 1. PSAM Hardware Design Figure 1 CS chip selection Signal SCK clock signal Data input from the MISO master device and output from the device Data output from the MOSI master device and input from the device 2. PSAM Software Design Figure 2 (1) PSAM Application You only need to call the API function. (2) PSAM API The main task of t

The last 2 weeks have been debugging IIC and SPI bus equipment, here record 2 kinds of bus, in case of forgetting. One IIC Bus The abbreviation of I2c--inter-ic serial Bus is the serial transmission bus between chips introduced by Philips company. It implements duplex synchronous data transfer with 1 serial data cables (SDA) and 1 serial clock lines (SCL). The utility model has the advantages of less interface line, simpler control mode, smaller devic

ObjectiveAs I said earlier, STM32 's timer function is very powerful, today to summarize its other "powerful" function: Tim's comparison output function, Output adjustable PWM waveform. Directly calling the function interface "TIM2_CH1_PWM (uint32_t Freq, uint16_t dutycycle)" The incoming frequency and duty ratio can output the specified waveform.The direct call I provide for software engineering is relatively simple to achieve the desired

clock).An important use of counter channels is the generation of precisely timed pulses.There is variations of this use– "one-pulse" pulses,In which a single pulse are generated, and pulse width modulation, in which a series of pulses are generated with the Counte R Uev period.The pulse width is controlled by the Capture/compare Register (CCR).For example, the channel output (OCXREF) could tied to whether the CNT register was greater (or less) than the Compare regist Er.In Figure 10.4 We illust

Description Code 1 description Using stm8s internal clock (HSI); PWM mode 2; Duty ratio is 50%, frequency is 2Hz (convenient test LED lamp); PD2 The LED lights, PD2 port output PWM wave; System clock Initialization is important: CLK_CKDIVR |= 0x08; 2 Code/*tim2_ch3 PWMPD2 output*/#include voidClk_init (void){Clk_ickr|=0x01;//Enable internal high-speed clock HSI

In a twinkling of an eye, we have arrived at the last class-PWM-provided by the mini2440 manufacturer. The driver uses the timer 0 to generate the PWM pulse signal, and the gpb0 pin output is connected to the buzzer. The Code is as follows: # Include # Include # Include # Include # Include # Include # Include # Include # Include # Include # Include # Include # Include # Include # Include # Include # Incl