自1980年以來，工業用通訊協定的趨勢為各個公司依照自己的應用領域而發展出不同的Fieldbus標準，在這些Fieldbus標準中卻存在許多缺點，因此發展出即時乙太網路。在即時乙太網路中，乙太網路控制自動化技術具有最佳的即時性和頻寬的高利用率，因此應用最為廣泛。在乙太網路控制自動化技術網路中，EtherCAT主站為了能對高精度EtherCAT從站馬達進行即時控制，EtherCAT主站需要能夠排程週期性即時任務，但是，常見的開源EtherCAT主站軟體堆疊都是在Linux平台進行開發，如果要提供排程週期性即時任務，則必須搭配即時擴充模組。為了改善EtherCAT主站排程週期性即時任務的精準度問題，本文透過修改SOEM主站開源軟體堆疊與FreeRTOS即時作業系統和FreeRTOS即時作業系統與Zedboard硬體之間的介面來開發出EtherCAT主站，如此一來，EtherCAT主站擁有排程週期性即時任務能力，進而能對高精度EtherCAT從站馬達進行即時同步控制。本文在Zedboard硬體上實現EtherCAT主站，並且針對EtherCAT主站進行任務排程抖動時間量測，最大的排程抖動時間為1.929μs，這足以應付即時控制應用。本文探討EtherCAT主站向高精度EtherCAT從站馬達進行即時同步控制會遇到的問題，並開發出EtherCAT主站能夠以125μs即時週期時間向高精度EtherCAT從站馬達進行即時同步控制；我們也將ZedBoard硬體、FreeRTOS即時作業系統和SOEM軟體堆層共三層進行整合，並降低排程抖動時間。

Since 1980, the trend in industrial communication protocols has been to develop fieldbus standards in accordance with the applications in use. Real-Time Ethernet was developed to address the numerous shortcomings of conventional fieldbus standards. EtherCAT is the most widely applied Real-Time Ethernet protocol, due to its real-time operability, synchronization performance, and high bandwidth utilization. However, EtherCAT requires the scheduling of periodic real-time tasks to enable the synchronization of multiple high-precision slave motors used for real-time control. Most existing open-source EtherCAT master software stacks are on the Linux platform, and therefore require specific extensions to enable the precision scheduling of periodic real-time tasks. The development of the EtherCAT Master Architecture has opened the door to the scheduling of periodic real-time tasks. Implementation of the EtherCAT embedded master is achieved by modifying interfaces between SOEM software stack and FreeRTOS RTOS and between FreeRTOS RTOS and ZedBoard hardware. These schemes have been shown to reduce maximum scheduling jitter to just 1.929μs. In this thesis, we discuss various issues encountered in the control and synchronization of multiple high-precision EtherCAT slave motors. We developed an EtherCAT embedded master that enables the scheduling of periodic real-time tasks during every 125μs real-time period. The three basic layers (SOEM Software Stack, FreeRTOS RTOS and ZedBoard hardware) are integrated and scheduling jitter is greatly reduced.

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