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The Zynq Processing System (PS), featuring an ARM hard core, offers a powerful platform for embedded applications. This article explores a fundamental method for controlling peripheral hardware from the PS: driving a chasing LED sequence through General Purpose Input/Output (GPIO) functionality. Leveraging a pre-configured GPIO IP core within t ...

Virtual Machine and Operating System Setup Establishing a stable development environment is the prerequisite for embedded Linux work. Ubuntu 20.04 LTS is recommended for compatibility with Loongson toolchains. VMware Configuration Install VMware Workstation on the host machine. Create a new virtual machine using the Ubuntu 20.04 ISO image. All ...

This article demonstrates basic STM32 GPIO control by blinking an onboard LED using both the Standard Peripheral Library and direct register manipulation. The target hardware uses the PC13 pin to drive the LED: a low output turns the LED on, a high output turns it off. All code is developed on an STM32F103 minimum system board. Schematic Analys ...

An interrupt is a mechanism that temporarily suspends the main program execution when a specific trigger condition occurs (interrupt source). The CPU then jumps to handle the interrupt service routine (ISR) and returns to the paused location after completion. Interrupt priority determines the order of handling when multiple interrupts occur sim ...

In Linux kernel development, spinlocks are essential synchronization primitives for protecting shared resources in interrupt contexts. This article demonstrates how to implement interrupt-safe spinlocks in a character device driver for controlling GPIO-based LEDs. We'll explore the use of spinlock functions that save and restore interrupt state ...

STM32F103 GPIO Programming Fundamentals Overview In the previous article, we discussed the reset and clock configuration for the STM32F103C8T6 minimal system. At this point, the system clock (SYSCLK) has been configured to 72MHz through a 9x multiplication of the external 8MHz high-speed oscillator (HSE) using the PLL. With the minimal system ...

Project Directory Structure Key project directories for STM32MP157 development: Buildroot root filesystem: /home/developer/projects/stm32mp157/rootfs NFS root fliesystem: /home/developer/projects/nfs/rootfs Linux source code: /home/developer/projects/linux-5.4.31 Device tree: /home/developer/projects/linux-5.4.31/arch/arm/boot/dts/stm32mp157-a ...

Kernel Space GPIO ManipulationFor the FMQL45T900 platform based on the Zynq-7000 architecture, controlling pins from the kernel space requires determining the correct GPIO index. When utilizing EMIO5 exported from Vivado, the corresponding system GPIO number calculates to 431. The device tree mapping for this pin appears as <&portc 5 0x0 ...

Overview of GPIO Input Modes 1.1 Button Basics Mechanical buttons are common digital input devices that close a circuit when pressed and open it when released. Due to the physical nature of their internal spring contacts, they exhibit bounce—a series of rapid on/off transitions during state changes. This requires software or hardware debounc ...

General Purpose Input/Output (GPIO) pins typically operate with in a logic voltage range of 0 to 3.3V. While certain inputs may tolerate 5V, output stages are strictly limited to the 3.3V supply. To control higher-power devices such as motors or relays, an external driver circuit must be integrated between the MCU pin and the load. Hardware Arc ...