4.2 Timer Pacer Mode

The digital I/O access control is clocked by timer pacer, which is generated by an interval programming timer/counter chip 8254. There are three timers on the 8254. The timer 0 is used to generate timer pacer for digital input, and timer 1 is used for digital output. The configuration is illustrated as below.

 

8254 Timer/Counter

 

CLK0

Timer 0

“H”

GATE0

OUT0

 

 

 

CLK1

Timer 1

“H”

 

GATE1

OUT1

4MHz Clock

CLK2

Timer 2

“H”

OUT2

GATE2

The operation sequences are:

1. Define the frequency (timer pacer rate)

Digital Input Timer Pacer

Digital Output Timer Pacer

2.The digital input data are saved in FIFO after a timer pacer pulse is generated. The sampling is controlled by timer pacer.

3.The data saved in FIFO will be transferred to main memory of your computer system directly and automatically. This is controlled by bus mastering DMA control, this function is supported by PCI controller chip.

The operation flow is show as following:

8254 Timer/Counter

 

 

 

 

 

1

 

 

 

 

 

 

Timer 0

 

 

 

CLK0

 

 

To Digital Input Trigger

 

 

 

 

 

GATE0

 

OUT0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Latch Digital Input

PC's Main Memory

2

3

Bus mastering

Digital Input FIFO

DMA data Transfer

24 Operation Theorem

Page 34
Image 34
Intel cPCI-7200 manual Timer Pacer Mode, 24 ∙ Operation Theorem

PCI-7200, cPCI-7200 specifications

The Intel cPCI-7200 is a high-performance, rugged computing platform designed to meet the demands of embedded and telecommunications applications. As a part of Intel’s CompactPCI family, the cPCI-7200 highlights the commitment to providing advanced processing capabilities in a flexible and modular form factor.

One of the standout features of the cPCI-7200 is its powerful multicore processing capabilities. It is equipped with Intel's latest x86 architecture, offering multiple cores that enable efficient execution of parallel tasks. This makes the cPCI-7200 particularly suitable for applications requiring real-time processing, such as network and communication systems. Additionally, the system supports high-speed data transfer, essential for bandwidth-intensive applications.

The cPCI-7200 also integrates advanced I/O technologies, ensuring that users can connect various peripherals and devices. With support for PCI Express, Ethernet, and other high-speed interfaces, the system provides a robust communication backbone for data-intensive applications. The modular design of CompactPCI allows for easy expansion, accommodating custom I/O cards as per specific application needs.

Built to function in harsh environments, the cPCI-7200 is designed with ruggedness in mind. It meets stringent environmental standards, which include resistance to shock, vibration, and temperature extremes. This makes the platform especially suitable for deployment in aerospace, military, and industrial settings where reliability is critical.

Furthermore, the Intel cPCI-7200 incorporates extensive power management features, which enhance overall system efficiency and reduce energy consumption. The adaptive power management capabilities enable the system to adjust power usage based on workload requirements, making it an eco-friendly option in comparison to other embedded systems.

Another significant characteristic of the cPCI-7200 is its scalability. The system can accommodate varying performance levels depending on application demands. Users can select from various processing options and add or remove resources as required, making this platform not only versatile but also cost-effective in the long run.

In summary, the Intel cPCI-7200 is a powerful, flexible, and rugged computing solution that caters to the evolving needs of embedded and telecommunications markets. With its advanced processing capabilities, extensive I/O options, rugged construction, energy-efficient design, and scalable architecture, it stands out as a reliable choice for developers looking to build high-performance applications in various challenging environments.