工業(yè)觸摸屏?xí)r代的到來

　　有開關(guān)和按鈕，由車輪和滑塊驅(qū)動(dòng)的線性或旋轉(zhuǎn)電位器，工業(yè)控制面板是機(jī)械運(yùn)動(dòng)場(chǎng)。作為機(jī)械，他們有可能成為問題的根源，從焊接接頭到運(yùn)動(dòng)部件。為一組特定的控制任務(wù)而構(gòu)建，這些板很難，如果不是不可能的話，可以重新配置。他們不容易學(xué)會(huì)如何使用，而且對(duì)于復(fù)雜的操作，常常伴隨著屏幕顯示設(shè)備狀態(tài)。

　　今天，這些都是消失的品種。相反，新的安裝完全是固態(tài)的，它們使用GUI（圖形用戶界面）驅(qū)動(dòng)的顯示屏幕上的觸摸屏。通過改變屏幕圖像，觸摸屏上面的區(qū)域可視地鏈接到不同的功能。這意味著，以及可重構(gòu)，系統(tǒng)可以指導(dǎo)用戶通過操作，也許在啟動(dòng)或關(guān)閉，也許當(dāng)一些不尋常的事情發(fā)生。雖然這種方法的優(yōu)點(diǎn)是界面更健壯、更易于清洗和更廣泛的環(huán)境耐受性，但它的代價(jià)是：軟件和復(fù)雜的軟件。

　　Of course， the different equipment， controlled by the screens， is itself managed by processors and software. The individual pieces of machinery communicate with each other and the overall system controller over some kind of bus， like CAN or Industrial Ethernet. Usually there is a strong element of real-time control needed and the applications may be safety critical， so the architecture of the entire system needs to be designed to segregate the touch screen controller and GUI from the overall system data， except through a secure defined interface. In this way， any issues with the GUI software will have no effect on the safety of the overall system or individual pieces of equipment.

　　This segregation might be caused by running all the GUI and touch screen activities on a separate processor running a general purpose operating system while the control activities operate on a real time operating system on its own processor. The processors might be physically separate devices， separate cores on a single chip or virtual cores created by virtualization software.

　　In this article， although we will be looking at physically separate controllers， much of the discussion will also be relevant to a touch screen controller running in a virtual core.