• Vending industry
• /
• v.8 no.3
• /
• pp.27-27
• /
• 2008

• Transactions of the Korean Society of Automotive Engineers
• /
• v.4 no.6
• /
• pp.196-204
• /
• 1996

The simplified dynamic models of the timer assembly in the diesel engine fuel injection system were developed. The first order system with time delay was assumed and the various parameters in this model were obtained by experimental data. These simplified dynamic models were used for the development of control algorithm of the injection timing control system. The PI control algorithm was modified to include the anti-windup property and disturbance compensation. This modified PI control algorithm was used for the control of the injection timing. Improved control accuracy and reduced control efforts were observed.

• Proceedings of the KIEE Conference
• /
• 2011.07a
• /
• pp.1798-1799
• /
• 2011

In this paper, A new cost-effective and accurate input noise rejection method for High Speed Counter module of PLC (Programmable Logic Controller) is proposed. By using combination of simple additional logic circuit and the Timer Pulse function of general purpose MPU, Cost-effectiveness and improvement of accuracy of filtering function can be achieved. This proposed method is verified by simulation. This proposed method is much useful for simple industrial controller based on simple microprocessor because of simplicity, accuracy and low cost.

• Proceedings of the Korean Information Science Society Conference
• /
• 2002.04a
• /
• pp.373-375
• /
• 2002

리눅스 컴퓨터 시스템에 실시간 웅용프로그램들을 실행할 경우, 실시간 응용프로그램 자체의 내부나 하부에 실시간 시스템 지원을 위한 엔진을 내장하고 있어야 만다. 그러나 기존의 리눅스 시스템들에 실시간 웅용프로그램을 적용하기 위만 실시간성을 보장 받기 위해서는 스케줄러의 실시간성 빈약 등으로 인해 운영체제의 수정이 불가피한 상황이다. 또한 운영체제의 수정은 호환성의 결여라는 문제를 야기시킨다. 이를 위해 사용하는 방식이 Middleware 방식이다. 실시간 시스템 지원 Middleware 는 운영체제와 실시간 지원 응용프로그램 사이에 위치하여 운영체제 자제가 가지고 있는 부족한 실시간성을 보완하여 주고, 응용프로그램이 적절하고 효과적으로 시스템 서비스들을 이용할 수 있게 해준다. 본 논문에서는 Middleware가 부족간 실시간성을 보완하기 위하여 사용할 수 있는 Middleware 스케줄러의 방식에 대하여 논하고, 효율적인 설계방식을 제안한다.

• Journal of Information Technology Services
• /
• v.12 no.3
• /
• pp.379-387
• /
• 2013

This paper describes a scheme of motor control for Quadcopter with Android phone instead of a dedicated controller. Basically, user's requests (channel and speed) are inquired and transferred to the Quadcopter with Android phone, then the embedded Linux system receives them and controls the motor speed of corresponding channel. We have designed and implemented an App. for user interface and the modules of device driver and timer ISR for the motor control. Finally, we have up-loaded the App. and the modules to an Android (ver.4.0) phone and ARM processor (S3C6410)-based embedded board respectively, and reviewed the functional correctness by testing the motor control of Quadcopter.

• The Transactions of the Korean Institute of Electrical Engineers D
• /
• v.51 no.7
• /
• pp.279-285
• /
• 2002

This Paper deals with the economical equipment control which is used by internet network system at the industrial workplace. If the control devices can be accessed by internet, we can have the developed possibility of work conditions. in this paper, we presented the advanced digital timer which has a communication function to control and observe panel to realize control solution based on internet to be easily applicable at workplace with low cost, and we used RS-485 serial communication module to have parallel expansibility and safety. And, this system was experimented and designed for easy system management and status check from remote station through internet. As the result for experiment, the circuit configuration would be more simplified than the existing, and it is expected that multi connection control and monitoring can be simply implemented with low cost equipment at industrial workplace.

• Proceedings of the IEEK Conference
• /
• 1998.06a
• /
• pp.839-842
• /
• 1998

The wide spread of multimedia system demands a large viewin gdesply device which can inform a message to many peoples in open area. This paper is about the design, simulating and testing of a large viewing LED pannel control ASIC(application specific integrated circuit). This LED pannel control ASIC runs on 16 bit microprocessor MC68EC000 and has following functions:16 line interlaced LED pannel controller, memory controller, 16 channel priority inerrupt controller, 2 channel direct memory access controller, 2 channel 12 bit clock and timer, 2 channel infrared remocon receiver, 2 channel RS-232C with 16byte FIFO, IBM PC/AT compatible keyboard interface, battery backuped real time clock, ISA bus controller, battery backuped 256 byte SRAM and watech dog timer. The 0.6micron CMOS sea of gate is used to design the ASIC in amount of about 39,000 gates.

• 제어로봇시스템학회:학술대회논문집
• /
• 2001.10a
• /
• pp.57.2-57
• /
• 2001

Timed token protocols inadequately provide periodic communication service, although this is crucial for hard real time systems. We propose an approach to guaranteeing periodic communication service on a timed token protocol network. In this approach, we allocate bandwidth to each node so that the summation of bandwidth allocations is Target Token Rotation Time (TTRT). If a node cannot consume the allocated time, the residual time can be used by other nodes for non-periodic service using a timer which contains the unused time value and is appended to the token. This approach can always guarantee transmission of real-time messages before their deadlines when the network utilization is less than 50%.

• Journal of Institute of Control, Robotics and Systems
• /
• v.9 no.12
• /
• pp.1055-1064
• /
• 2003

In many automated systems, such as manufacturing systems and process plants, a fieldbus is a very important component for the exchange of various and sometimes crucial information. Some of the information has a tendency to rapidly lose its value as time elapses after its creation. Such information or data is called real-time data that includes sensor values and control commands. In order to deliver these data in time, the fieldbus network should be tailored to have short delay with respect to the individual time limit of various data. Fine-tuning the network for a given traffic requires the knowledge on the relationship between the protocol parameters such as timer values and the performance measure such as network delay. This paper presents a mathematical performance model to calculate communication delays of the Profibus-FMS network when the timer value and the traffic characteristics are given.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2017.01a
• /
• pp.3-4
• /
• 2017

본 논문에서는 가상화 기술을 지원하는 ARMv7 Cortex-A15 프로세서가 탑재된 임베디드 보드를 위한 실시간 운영체제(RTOS) 구현을 위한 방법을 제안한다. ARM Cortex-A15 프로세서가 지원하는 Generic Interrupt Controller와 Generic Timer에 대해 알아보고, 가상화 시스템에서 인터럽트 오버헤드를 줄이는 GICv2와 가상 타이머인 Generic Timer를 사용하여 실시간 운영체제인 FreeRTOS를 임베디드 보드에 이식하였다.