200941288 . 玖、發明說明： 【發明所屬之技術領域】 本發明關於多電滕切換器（KVM，Keyboard-Video-Mouse) ’ 尤指一種能為耦接至其之電腦，提供並更新螢幕的擴充顯示識 別資料（EDID，Extended Display Identification Data)之多電滕切 換器及方法。 【先前技術】 在一般電腦更換螢幕且直接連接於螢幕時，並不會自動 ® 更新擴充顯示識別資料。而是必須先將電腦關機，讓電腦重新 開機後，電腦方可讀取螢幕之擴充顯示識別資料。 對於支援螢幕熱插拔偵測（HPD ’ Hot Plug Detection)之電 腦，例如麥金塔（MAC)電腦，當麥金塔電腦更換螢幕且直接連 接於螢幕時，熱插拔偵測訊號偵測到變化時，會自行更新擴充 顯示識別資料。故只要顯示卡支援熱插拔偵測且會自行更新擴 充顯示識別資料，當更換螢幕時，並不需將電腦關機。 多電腦切換器係一種以一組鍵盤、螢幕以及滑鼠等週邊裝 〇 置控制複數台電腦之裝置。鍵盤及滑鼠通常只要連接至多電臈 切換器，即可馬上使用，至於螢幕在連接至多電腦切換器之 後，多電腦切換器會對螢幕詢問擴充顯示識別資料，並將螢幕 之擴充顯示識別資料寫入多電腦切換器的記憶體，確保所有連 接至多電腦切換器開機時，均能讀取到螢幕正確的擴充顯示識 別資料。 目前的多電腦切換器在開機時，會進行螢幕擴充顯示識別 資料的讀取，並以螢幕之擴充顯示識別資料直接更新其記憶體 內之擴充顯示識別資料。 5 200941288 - 如多電腦切換器在開機後，又再更換或插拔螢幕時，多電 腦切換器並不會自動更新記憶體内之擴充顯示識別資料，導致 記憶體内之擴充顯示識別資料不同於螢幕之擴充顯示識別資 料時，耦接至多電腦切換器的電腦讀取到非螢幕真正的擴充顯 示識別資料，因此導致問題的產生，例如螢幕無法顯示畫面、 無法支援最佳之解析度、出畫延遲等問題。 對於支援螢幕熱插拔偵測之電腦，例如麥金塔電腦，多電 腦切換器在切換時，相當於螢幕有插拔之動作，麥金塔電腦會 ® 偵測該插拔之現象，因此會進行擴充顯示識別資料的重新讀 取，該重新讀取的動作會造成螢幕在顯示畫面時，延遲5至8 秒的時間，造成無法快速出畫之情形。另外，當所有耦接至多 電腦切換器的電腦均為支援螢幕熱插拔偵測之電腦時，一旦螢 幕進行更換或插拔動作時，須先將多電滕切換器及所有電腦關 機，讓多電腦切換器重新開機、讀取螢幕之擴充顯示識別資 料，並更新記憶體内之擴充顯示識別資料後，才能讓電腦讀取 到正確的擴充顯示識別資料，所以對於支援螢幕熱插拔偵測之 〇 電腦，更換或插拔螢幕於多電腦切換器時是個棘手且需要處理 的複雜程序問題》 【發明内容】 本發明主要目的在於提供一種多電腦切換器，當多電腦切 換器開機時，會比對螢幕之擴充顯示識別資料與儲存於多電腦 切換器内之記憶體的擴充顯示識別資料是否相同，當兩者相同 時，不作更新的動作，當兩者不同時，以螢幕之擴充顯示識別 資料覆寫記憶體内之擴充顯示識別資料，完成更新的動作。 本發明另一目的在於提供一種多電腦切換器，當螢幕有插 200941288 - 拔或更換之情況時，能夠自動比對螢幕之擴充顯示識別資料與 儲存於多電腦切換器内之記憶體的擴充顯示識別資料，確認是 否需進行記憶體内之擴充顯示識別資料的更新。 本發明又一目的在於提供一種多電腦切換器，能夠讓使用 者以熱鍵(hot key)方式，將螢幕之擴充顯示識別資料手動覆寫 記憶體内之擴充顯示識別資料，完成手動更新的動作。 本發明又一目的在於提供一種多電腦切換器，對於支援螢 幕熱插拔偵測之電腦，當多電腦切換器在切換時，能夠達成快 • 速出畫之目的。另外對該類型之電腦，能進行熱插拔偵測控 制，自動更新擴充顯示識別資料。 本發明又一目的在於揭露一種提供螢幕之擴充顯示識別資 料之方法，能使耦接至多電腦切換器之電腦，得到螢幕正確之 擴充顯示識別資料。 本發明之多電腦切換器，耦接至少一電腦至一螢幕，其中 該螢幕具有一第一擴充顯示識別資料，多電腦切換器包括一處 理器、至少一記憶體以及至少一切換器。處理器分別耦接至螢 © 幕及電腦，用以接收第一擴充顯示識別資料，並且輸出一熱插 拔偵測訊號至電腦。記憶體耦接至處理器，用以儲存一第二擴 充顯示識別資料。切換器選擇性地耦接電腦至螢幕及記憶體之 一，用以提供第一擴充顯示識別資料或第二擴充顯示識別資料 給電腦。 當多電腦切換器開機、偵測到螢幕插拔或更換、或是接收 到外部控制訊號時，處理器比對第一擴充顯示識別資料與第二 擴充顯示識別資料是否相同。當處理器比對第一擴充顯示識別 資料與第二擴充顯示識別資料不同時，控制記憶體以第一擴充 7 200941288 - 顯示識別資料覆寫第二擴充顯示識別資料。同時藉由熱插拔偵 測訊號之控制，使電腦讀取正確之擴充顯示識別資料。 當多電腦切換器偵測到螢幕插拔或更換、或是接收到外部 控制訊號時，而處理器比對第一擴充顯示識別資料與第二擴充 顯示識別資料相同時，處理器藉由熱插拔偵測訊號之控制，使 電腦讀取記憶體之第二擴充顯示識別資料，即讀取到螢幕正確 之擴充顯示識別資料。 本發明之可提供螢幕之擴充顯示識別資料之方法，包括下 ⑩列步驟： 詢問螢幕之第一擴充顯示識別資料； 將第一擴充顯示識別資料，與儲存於至少一記憶體之一第 二擴充顯示識別資料予以比對；以及 該比對結果不同時，以第一擴充顯示識別資料覆寫第二擴 充顯示識別資料，並傳送一熱插拔偵測訊號至電腦，使電腦自 記憶體讀取第一擴充顯示識別資料。或者是，該比對結果相同 時，傳送一熱插拔偵測訊號至電腦，使電腦自記憶體讀取第二 〇 擴充顯示識別資料。 為讓本發明之上述和其他目的、特徵、和優點能更明顯易 懂，配合所附圖式，作詳細說明如下： 【實施方式】 請參閱第1A圖，係依據本發明第一實施例的多電腦切換 器10應用之方塊圖。多電腦切換器10分別耦接電腦150、152 至螢幕160,螢幕160具有一第一擴充顯示識別資料。多電腦 切換器10包括一處理器100、兩記憶體110、112、兩切換器 120、122、一多工器130、以及一影像訊號介面切換器132。 8 200941288 處理器100分別耦接至螢幕160以及電臞15〇、152，用以接收 螢幕160之第一擴充顯示識別資料，並可輸出一熱插拔偵測訊 號（HPD ’ Hot Plug Detection)140 至電觸 15〇、152。記憶想 110、 112透過多工器130耦接至處理器1〇〇,用以儲存一第二擴充顯 示識別資料。其中記憶體110、112可為揮發性記憶體或非揮發 性記憶體。要說明的是，記憶體110、112也可不透過多工器 130，而分別直接與處理器100耦接。多工器13〇之功能是提 供處理器100將螢幕160之第一擴充顯示識別資料透過切換的200941288 . Description of the Invention: [Technical Field of the Invention] The present invention relates to a KVM (Keyboard-Video-Mouse), and more particularly to an extension that provides and updates a screen for a computer coupled thereto. A multi-switch and method for displaying an Extended Display Identification Data (EDID). [Prior Art] When a normal computer replaces the screen and is directly connected to the screen, it does not automatically update the display identification data. Instead, the computer must be turned off first, and after the computer is turned back on, the computer can read the extended display identification data of the screen. For computers that support HPD 'Hot Plug Detection', such as Macintosh computers, when the Macintosh computer replaces the screen and is directly connected to the screen, the hot plug detection signal is detected. When the change is made, the extended display identification data will be updated by itself. Therefore, as long as the display card supports hot plug detection and the update display identification data is updated by itself, the computer does not need to be turned off when the screen is replaced. A KVM switch is a device that controls a plurality of computers with a set of peripheral devices such as a keyboard, a screen, and a mouse. The keyboard and mouse are usually connected to the multi-switch, and can be used immediately. After the screen is connected to the KVM switch, the KVM switch will expand the display identification data and write the extended display identification data. Enter the memory of the multi-computer switch to ensure that all connected to the KVM switch can read the correct extended display identification data. At the time of power-on, the current KVM switch will read the display information of the screen display, and display the identification data directly in the memory to display the extended display identification data in the memory. 5 200941288 - If the switch is replaced or plugged in after the PC switch is turned on, the KVM does not automatically update the extended display identification data in the memory, resulting in an expanded display identification data in the memory. When the screen is expanded to display the identification data, the computer coupled to the KVM switch reads the non-screen real extended display identification data, which causes problems, such as the screen cannot display the screen, cannot support the best resolution, and draws the picture. Delay and other issues. For computers that support screen hot plug detection, such as Macintosh computers, when the switch is switched, it is equivalent to the action of plugging and unplugging the screen. The Macintosh computer will detect the plugging and unplugging phenomenon. The re-reading of the extended display identification data is performed, and the re-reading operation causes the screen to be delayed by 5 to 8 seconds when the screen is displayed, resulting in a situation in which the drawing cannot be quickly performed. In addition, when all computers connected to the KVM switch are computers that support hot-swap detection, once the screen is replaced or plugged or unplugged, the multi-switch and all computers must be shut down first. After the computer switcher is rebooted, the extended display of the screen is displayed, and the extended display identification data in the memory is updated, the computer can read the correct extended display identification data, so that the hot-swap detection is supported. 〇Computer, replacing or plugging and unplugging the screen on the KVM switch is a tricky and complicated program problem to be handled. [ SUMMARY OF THE INVENTION The main object of the present invention is to provide a KVM switch, which is more than when the KVM switch is turned on. Whether the identification data of the extended display of the screen and the expanded display identification data of the memory stored in the KVM switch are the same, when the two are the same, the update operation is not performed, and when the two are different, the identification data is displayed by the expansion of the screen. Overwrite the expanded display in the memory to display the identification data and complete the update action. Another object of the present invention is to provide a multi-computer switch capable of automatically displaying the identification information of the expanded display and the expanded display of the memory stored in the KVM switch when the screen is inserted into the 200941288 - when the device is removed or replaced. Identify the data and confirm whether it is necessary to update the memory to display the identification data. Another object of the present invention is to provide a KVM switch that allows a user to manually overwrite the extended display identification data in the memory by a hot key to complete the manual update operation. . Another object of the present invention is to provide a KVM switch. For a computer that supports hot swap detection of a screen, when the KVM switch is switched, it can achieve the purpose of fast drawing. In addition, this type of computer can perform hot plug detection control and automatically update and display the identification data. Another object of the present invention is to provide a method for providing extended display identification information of a screen, which can be coupled to a computer of a KVM switch to obtain a display and identification data that is correctly displayed on the screen. The KVM switch of the present invention is coupled to at least one computer to a screen, wherein the screen has a first extended display identification data, and the KVM switch includes a processor, at least one memory, and at least one switch. The processor is coupled to the screen and the computer for receiving the first extended display identification data and outputting a hot plug detection signal to the computer. The memory is coupled to the processor for storing a second extended display identification data. The switch selectively couples the computer to one of the screen and the memory to provide the first extended display identification data or the second extended display identification data to the computer. When the KVM switch is turned on, the screen is inserted or removed, or the external control signal is received, the processor compares whether the first extended display identification data and the second extended display identification data are the same. When the processor compares the first extended display identification data with the second extended display identification data, the control memory overwrites the second extended display identification data with the first extension 7 200941288 - display identification data. At the same time, by the control of the hot plug detection signal, the computer reads the correct extended display identification data. When the KVM switch detects the insertion or removal of the screen or receives an external control signal, and the processor compares the first extended display identification data with the second extended display identification data, the processor is hot-plugged. The control of the detection signal is extracted, so that the computer reads the second extended display identification data of the memory, that is, reads the correct display identification data to the screen. The method for providing extended display identification data of the screen comprises the following steps: querying the first extended display identification data of the screen; displaying the first extended display identification data and storing the second expansion in at least one memory Displaying the identification data for comparison; and when the comparison result is different, the second extended display identification data is overwritten by the first extended display identification data, and a hot plug detection signal is transmitted to the computer to enable the computer to read from the memory The first extension displays the identification data. Alternatively, when the comparison result is the same, a hot plug detection signal is transmitted to the computer, so that the computer reads the second 自 from the memory to expand the display identification data. The above and other objects, features, and advantages of the present invention will become more apparent from the description of the accompanying drawings. FIG. A block diagram of the application of the KVM switch 10. The KVM switch 10 is coupled to the computer 150, 152 to the screen 160, respectively, and the screen 160 has a first extended display identification data. The multi-computer switch 10 includes a processor 100, two memories 110, 112, two switches 120, 122, a multiplexer 130, and an image signal interface switch 132. 8 200941288 The processor 100 is coupled to the screen 160 and the switch 15 152 and 152 respectively for receiving the first extended display identification data of the screen 160 and outputting a hot plug detection signal (HPD 'Hot Plug Detection) 140. To the electric touch 15〇, 152. The memory 110, 112 is coupled to the processor 1 through the multiplexer 130 for storing a second extended display identification data. The memory 110, 112 may be a volatile memory or a non-volatile memory. It should be noted that the memory 110, 112 may also be directly coupled to the processor 100 without passing through the multiplexer 130. The function of the multiplexer 13 is to provide the processor 100 to switch the first extended display identification data of the screen 160 through the switch.
A 方式分別寫入記憶體110、112。切換器120能選擇性地耦接電 腦150至螢幕160及記憶體110之一，用以提供電腦150第一 擴充顯示識別資料或第二擴充顯示識別資料。切換器122能選 擇性地耗接電膜152至螢幕160及記憶艘112之一，用以提供 電腦152第一擴充顯示識別資料或第二擴充顯示識別資料。本 實施例中，多電腦切換器10可切換至電腦15〇，所以電膘150 從記憶體110或螢幕160讀取第一或第二擴充顯示識別資料， 電腦152則從記憶體112讀取第二擴充顯示識別資料。影像訊 © 號介面切換器132係用以選擇電腦150及電腦152之其一，傳 送影音資料至螢幕160，如數位影像介面（DVI，Digital Video Interface)、高清晰度多媒趙介面（HDMI，High Definition Multimedia Interface)、視頻圖形陣列介面（VGA，Video Graphics Array Interface)。 當多電腦切換器10開機後，處理器100自動比對螢幕160 之第一擴充顯示識別資料與儲存於記憶體110、112内之第二擴 充顯示識別資料是否相同，當兩者相同時，處理器100即無須 作更新之動作。當兩者不同時，處理器100維持熱插拔偵測訊 9 200941288 - 號140為一第一準位傳送至電腦150、152，並以螢幕160之第 一擴充顯示識別資料透過多工器130分別覆寫記憶體110、112 内之第二擴充顯示識別資料，當記憶體110、112儲存完螢幕 160之第一擴充顯示識別資料後，處理器100將熱插拔偵測訊 號140由第一準位轉換為一第二準位。 本實施例中，第一準位係低於第二準位。請同時參閱第1B 圖，係處理器100傳送至電腦150、152之熱插拔偵測訊號140 波形圖。由圖中可知，熱插拔偵測訊號140係由低準位拉高至 ® 高準位。因此當處理器100比對出螢幕160與記憶體110、112 之擴充顯示識別資料不同時，先維持熱插拔偵測訊號140在低 準位，當記憶體110、112更新完成之後，再將熱插拔偵測訊號 140由低準位拉高為高準位。當多電腦切換器10從電腦150切 換至電腦152時，處理器100維持熱插拔偵測訊號140為第二 準位，本實施例中，係維持為高準位，維持準位不變的目的在 於針對支援螢幕熱插拔偵測之電腦，當多電腦切換器10切換 時，讓電腦150或152認為一直都有與螢幕160耦接，否則切 〇 換時電腦150或152會以為偵測到螢幕160插拔或更換而重新 讀取擴充顯示識別資料，造成出畫時間延遲多達數秒。要特別 說明的是，第一準位亦可高於第二準位，其處理過程與上述類 似。 需要注意的是，熱插拔偵測訊號140係可由高準位拉低至 低準位。因此當處理器100比對出螢幕160與記憶體110、112 之擴充顯示識別資料不同時，先維持熱插拔偵測訊號140在高 準位，當記憶體110、112更新完成之後，再將熱插拔偵測訊號 140由高準位拉低為低準位。當多電腦切換器10從電腦150切 200941288 - 換至電腦152時，處理器100維持熱插拔偵測訊號140為低準 位。 請參閱第2A圖，係依據本發明第二實施例的多電腦切換 器20應用之方塊圖。多電腦切換器20分別耦接電腦250、252 至螢幕260,螢幕260具有一第一擴充顯示識別資料。多電腦 切換器20包括一處理器200、兩記憶體210、212、兩切換器 220、222、一多工器230、以及一影像訊號介面切換器232。 處理器200分別耦接至螢幕260以及電腦250 ' 252，用以接收 ® 螢幕260之第一擴充顯示識別資料，並可輸出一熱插拔偵測訊 號240至電腦250、252。記憶體210、212透過多工器230耦 接至處理器200,用以儲存第二擴充顯示識別資料。其中記憶 體210、212可為揮發性記憶體或非揮發性記憶體。要說明的 是，記憶體210、212也可不透過多工器230,而分別直接與處 理器200耦接。多工器230之功能是提供處理器200將螢幕260 之第一擴充顯示識別資料透過切換的方式分別寫入記憶體 210、212。切換器220能選擇性地耦接電腦250至螢幕260及 © 記憶體210之一，用以提供電腦250第一擴充顯示識別資料或 第二擴充顯示識別資料。切換器222能選擇性地耦接電腦252 至螢幕260及記憶體212之一，用以提供電腦252第一擴充顯 示識別資料或第二擴充顯示識別資料。本實施例中，多電腦切 換器20可切換至電腦250,所以電腦250從記憶體210或螢幕 260讀取第一或第二擴充顯示識別資料，電腦252則從記憶體 212讀取第二擴充顯示識別資料。影像訊號介面切換器232係 用以選擇電腦250及電腦252之其一，傳送影音資料至螢幕 260,如數位影像介面、高清晰度多媒體介面、視頻圖形陣列 11 200941288 ^ 介面。 當處理器200偵測到螢幕260插拔或更換時，處理器200 比對第一擴充顯示識別資料與第二擴充顯示識別資料是否相 同；當兩者不同時，處理器200維持熱插拔偵測訊號240為一 第一準位傳送至電腦250、252，並以螢幕260之第一擴充顯示 識別資料透過多工器230分別覆寫記憶體210、212内之第二 擴充顯示識別資料，當記憶體210、212儲存完螢幕260之第 一擴充識別資料後，處理器200將熱插拔偵測訊號240由第一 ® 準位轉換為一第二準位，再轉換為第一準位，該兩次準位轉換 的熱插拔偵測訊號240，使電腦250或252認為其偵測到螢幕 260關機再開機，或者是偵測到螢幕260插拔或更換，而對多 電腦切換器20發出擴充顯示識別資料之請求，自記憶體210、 212讀取第一擴充顯示識別資料，達到讀取正確擴充顯示識別 資料之目的。 當處理器200比對螢幕260之第一擴充顯示識別資料與記 憶體210、212之第二擴充顯示識別資料相同時，處理器200 〇 將熱插拔偵測訊號240由第一準位轉換為第二準位，再轉換為 第一準位，如上所述，該兩次準位轉換的熱插拔偵測訊號240, 使電腦250或252認為其偵測到螢幕260關機再開機，或者是 偵測到螢幕260插拔或更換，而對多電腦切換器20發出擴充 顯示識別資料之請求，由於螢幕260之第一擴充顯示識別資料 與記憶體210、212之第二擴充顯示識別資料相同，因此直接 讀取記憶體210、212之第二擴充顯示識別資料，即達到讀取 螢幕260正確的擴充顯示識別資料之目的。The A mode is written to the memories 110 and 112, respectively. The switch 120 can be selectively coupled to the computer 150 to one of the screen 160 and the memory 110 for providing the first extended display identification data or the second extended display identification data of the computer 150. The switch 122 can selectively consume the film 152 to one of the screen 160 and the memory bank 112 for providing the first extended display identification data or the second extended display identification data of the computer 152. In this embodiment, the KVM switch 10 can be switched to the computer 15A, so the eMule 150 reads the first or second extended display identification data from the memory 110 or the screen 160, and the computer 152 reads the first from the memory 112. Second, expand the display identification data. The video interface interface switch 132 is used to select one of the computer 150 and the computer 152 to transmit video and audio data to the screen 160, such as a digital video interface (DVI, Digital Video Interface), and a high-definition multimedia interface (HDMI, High Definition Multimedia Interface), Video Graphics Array Interface (VGA). After the KVM switch 10 is turned on, the processor 100 automatically compares the first extended display identification data of the screen 160 with the second extended display identification data stored in the memory 110, 112. When the two are the same, the processing is performed. The device 100 does not need to be updated. When the two are different, the processor 100 maintains the hot plug detection signal 9 200941288 - the number 140 is transmitted to the computer 150, 152 for a first level, and displays the identification data through the multiplexer 130 with the first extension of the screen 160. The second extended display identification data in the memory 110, 112 is overwritten. After the memory 110, 112 stores the first extended display identification data of the screen 160, the processor 100 sets the hot plug detection signal 140 by the first The level is converted to a second level. In this embodiment, the first level is lower than the second level. Please also refer to FIG. 1B, which is a waveform diagram of the hot plug detection signal 140 transmitted by the processor 100 to the computers 150 and 152. As can be seen from the figure, the hot plug detection signal 140 is pulled from the low level to the high level. Therefore, when the processor 100 compares the display 160 and the extended display identification data of the memory 110 and 112, the hot plug detection signal 140 is maintained at a low level, and after the memory 110 and 112 are updated, the The hot plug detection signal 140 is pulled from the low level to the high level. When the KVM switch 10 is switched from the computer 150 to the computer 152, the processor 100 maintains the hot plug detection signal 140 as the second level. In this embodiment, the CPU 100 maintains the high level and maintains the same level. The purpose is to support the screen hot-swap detection computer. When the KVM switch 10 is switched, the computer 150 or 152 is always connected to the screen 160. Otherwise, the computer 150 or 152 will detect it. Re-reading the extended display identification data by inserting or replacing the screen 160 causes the drawing time to be delayed by several seconds. It should be particularly noted that the first level can also be higher than the second level, and the processing procedure is similar to the above. It should be noted that the hot plug detection signal 140 can be pulled down from the high level to the low level. Therefore, when the processor 100 compares the display 160 and the extended display identification data of the memory 110 and 112, the hot plug detection signal 140 is maintained at a high level, and after the memory 110 and 112 are updated, the The hot plug detection signal 140 is pulled from the high level to the low level. When the KVM switch 10 is switched from the computer 150 200941288 - to the computer 152, the processor 100 maintains the hot plug detection signal 140 at a low level. Referring to Fig. 2A, there is shown a block diagram of the application of the KVM switch 20 in accordance with the second embodiment of the present invention. The KVM switch 20 is coupled to the computers 250 and 252 to the screen 260, and the screen 260 has a first extended display identification data. The multi-computer switch 20 includes a processor 200, two memories 210, 212, two switches 220, 222, a multiplexer 230, and an image signal interface switch 232. The processor 200 is coupled to the screen 260 and the computer 250' 252 for receiving the first extended display identification data of the screen 260 and outputting a hot plug detection signal 240 to the computers 250 and 252. The memory 210, 212 is coupled to the processor 200 through the multiplexer 230 for storing the second extended display identification data. The memory 210, 212 may be a volatile memory or a non-volatile memory. It should be noted that the memory 210, 212 may also be directly coupled to the processor 200 without passing through the multiplexer 230. The function of the multiplexer 230 is to provide the processor 200 to write the first extended display identification data of the screen 260 into the memory 210, 212 by switching. The switch 220 can selectively couple the computer 250 to one of the screen 260 and the © memory 210 to provide the first expanded display identification data or the second extended display identification data of the computer 250. The switch 222 can selectively couple the computer 252 to one of the screen 260 and the memory 212 for providing the first extended display identification data or the second extended display identification data of the computer 252. In this embodiment, the KVM switch 20 can be switched to the computer 250, so the computer 250 reads the first or second extended display identification data from the memory 210 or the screen 260, and the computer 252 reads the second extension from the memory 212. Display identification data. The image signal interface switcher 232 is used to select one of the computer 250 and the computer 252 to transmit video and audio data to the screen 260, such as a digital image interface, a high definition multimedia interface, and a video graphics array 11 200941288 ^ interface. When the processor 200 detects that the screen 260 is plugged or unplugged or replaced, the processor 200 compares whether the first extended display identification data and the second extended display identification data are the same; when the two are different, the processor 200 maintains hot plug detection. The test signal 240 is transmitted to the computer 250 and 252 for a first level, and the first extended display identification data of the screen 260 is overwritten by the multiplexer 230 to respectively overwrite the second extended display identification data in the memory 210, 212. After the memory 210, 212 stores the first extended identification data of the screen 260, the processor 200 converts the hot plug detection signal 240 from the first level to the second level, and then converts to the first level. The hot swap detection signal 240 of the two level conversions causes the computer 250 or 252 to detect that the screen 260 is turned off and on, or to detect the insertion or removal of the screen 260, and to the KVM switch 20 The request for expanding the display identification data is sent, and the first extended display identification data is read from the memory 210, 212, so as to read the correct extended display identification data. When the processor 200 compares the first extended display identification data of the screen 260 with the second extended display identification data of the memory 210, 212, the processor 200 converts the hot plug detection signal 240 from the first level to the first level. The second level is converted to the first level. As described above, the two-level hot swap detection signal 240 causes the computer 250 or 252 to detect that the screen 260 is turned off and on, or The screen 260 is detected to be inserted or removed, and the KVM switch 20 is requested to expand the display identification data. Since the first extended display identification data of the screen 260 is the same as the second extended display identification data of the memory 210 and 212, Therefore, the second extended display identification data of the memory 210, 212 is directly read, that is, the purpose of reading the correct expanded display identification data of the screen 260 is achieved.
本實施例中，第一準位係高於第二準位。請同時參閱第2B 12 200941288 圖，係處理器200傳送至電腦250、252之熱插拔偵測訊號240 波形圖。由圖中可知，熱插拔偵測訊號240係由高準位拉低至 低準位，再拉高至高準位。因此當處理器200比對出螢幕260 與記憶體210、212之擴充顯示識別資料不同時，先維持熱插 拔偵測訊號240在高準位，當記憶體210、212更新完成之後， 將熱插拔偵測訊號240由高準位拉低至低準位，再拉高至高準 位，儼然如同一負脈波(pulse)。當處理器200比對出螢幕260 與記憶體210、212之擴充顯示識別資料相同時，不需要更新 ® 記憶體之擴充顯示識別資料（當然亦可直接以第一擴充顯示識 別資料覆蓋記憶體之第二擴充顯示識別資料），而先維持熱插拔 偵測訊號240在高準位，再將熱插拔偵測訊號240由高準位拉 低至低準位，再拉高至高準位，儼然如同一負脈波（pulse)。當 多電腦切換器20從電腦250切換至電腦252時，處理器200 維持熱插拔偵測訊號240為第一準位，本實施例中，係維持為 高準位，維持準位不變的目的在於針對支援螢幕熱插拔偵測之 電腦，當多電腦切換器20切換時，讓電腦250、252認為一直 〇 都有與螢幕260耦接，否則在多電腦切換器20進行切換時， 電腦250、252會以為偵測到螢幕260的插拔或更換，而重新 詢問並讀取擴充顯示識別資料，造成出畫時間延遲多達數秒。 要特別說明的是，第一準位亦可低於第二準位，其處理過程與 上述類似。 需要注意的是，熱插拔偵測訊號240係可由低準位拉高至 高準位，再拉低至低準位。因此當處理器200比對出螢幕260 與記憶體210、212之擴充顯示識別資料不同時，先維持熱插 拔偵測訊號240在低準位，當記憶體210、212更新完成之後， 13 200941288 將熱插拔偵測訊號240由低準位拉高至高準位，再拉低至低準 位，儼然如同一正脈波（pulse)。當處理器200比對出螢幕260 與記憶體210、212之擴充顯示識別資料相同時，不需要更新 記憶體之擴充顯示識別資料（當然亦可直接以第一擴充顯示識 別資料覆蓋記憶體之第二擴充顯示識別資料），而先維持熱插拔 偵測訊號240在低準位，再將熱插拔偵測訊號240由低準位拉 高至高準位，再拉低至低準位，儼然如同一正脈波（pulse)。當 多電腦切換器20從電腦250切換至電腦252時，處理器200 ❹ 維持熱插拔偵測訊號240為低準位。 請參閱第3A圖，係依據本發明第三實施例的多電腦切換 器30應用之方塊圖。多電腦切換器30分別耦接電腦350、352 至螢幕360,螢幕360具有一第一擴充顯示識別資料。鍵盤370 耦接至多電腦切換器30,用以產生一外部控制訊號至多電腦切 換器30。多電腦切換器30包括一處理器300、兩記憶體310、 312、兩切換器320、322、一多工器330、以及一影像訊號介 面切換器332。處理器300分別耦接至螢幕360以及電腦350、 ❹ 352，用以偵測鍵盤370傳送之外部控制訊號，接收螢幕360 之第一擴充顯示識別資料，並可輸出一熱插拔偵測訊號340至 電腦350、352。記憶體310、312透過多工器330耦接至處理 器300,用以儲存第二擴充顯示識別資料。記憶體310、3 12可 為揮發性記憶體或非揮發性記憶體。要說明的是，記憶體310、 312也可以不透過多工器330,而分別直接與處理器300耦接。 多工器330之功能是提供處理器300將螢幕360之第一擴充顯 示識別資料透過切換的方式分別寫入記憶體310、312。切換器 320能選擇性地耦接電腦350至螢幕360及記憶體310之一， 200941288 用以提供電腦350第一擴充顯示識別資料或第二擴充顯示識別 資料。切換器322能選擇性地耦接電腦352至螢幕360及記憶 體312之一，用以提供電腦352第一擴充顯示識別資料或第二 擴充顯示識別資料。本實施例中，多電腦切換器30可切換至 電腦350，所以電腦350從記憶體310或螢幕360讀取第一或 第二擴充顯示識別資料，電腦352則從記憶體312讀取第二擴 充顯示識別資料。影像訊號介面切換器332係用以選擇電腦350 及電腦352之其一，傳送影音資料至螢幕360，如數位影像介 ❿ 面、高清晰度多媒體介面、視頻圖形陣列介面。 當處理器300偵測到來自鍵盤370之外部控制訊號時，處 理器300比對第一擴充顯示識別資料與第二擴充顯示識別資料 是否相同；當兩者不同時，處理器300維持熱插拔偵測訊號340 為一第一準位傳送至電腦350、352，並以螢幕360之第一擴充 顯示識別資料透過多工器330分別覆寫記憶體310、312内之 第二擴充顯示識別資料，當記憶體310、312儲存完螢幕360 之第一擴充識別資料後，處理器300將熱插拔偵測訊號340由 〇 第一準位轉換為一第二準位，再轉換為第一準位，該兩次準位 轉換的熱插拔偵測訊號340，使電腦350或352認為其偵測到 螢幕360關機再開機，或者是偵測到螢幕插拔或更換，而對多 電腦切換器30發出擴充顯示識別資料之請求，自記憶體310、 312讀取第一擴充顯示識別資料，達到讀取正確擴充顯示識別 資料之目的。 當處理器300比對螢幕360之第一擴充顯示識別資料與記 憶體310、312之第二擴充顯示識別資料相同時，處理器300 將熱插拔偵測訊號340由第一準位轉換為第二準位，再轉換為 15 200941288 - 第一準位，如上所述，該兩次準位轉換的熱插拔偵測訊號340， 使電腦350或352認為其偵測到螢幕360關機再開機，或者是 偵測到螢幕360插拔或更換，而對多電腦切換器30發出擴充 顯示識別資料之請求，由於螢幕360之第一擴充顯示識別資料 與記憶體310、312之第二擴充顯示識別資料相同，因此直接 讀取記憶體310、312之第二擴充顯示識別資料，即達到讀取 螢幕360正確的擴充顯示識別資料之目的。 本實施例中，第一準位係高於第二準位。請同時參閱第3B ® 圖，係處理器300傳送至電腦350、352之熱插拔偵測訊號340 波形圖。由圖中可知，熱插拔偵測訊號340係由高準位拉低至 低準位，再拉高至高準位。因此當處理器300比對出螢幕360 與記憶體310、312之擴充顯示識別資料不同時，先維持熱插 拔偵測訊號340在高準位，當記憶體310、312更新完成之後， 將熱插拔偵測訊號340由高準位拉低至低準位，再拉高至高準 位，儼然如同一負脈波（pulse)。當處理器300比對出螢幕360 與記憶體310、312之擴充顯示識別資料相同時，不需要更新 〇 記憶體之擴充顯示識別資料（當然亦可直接以第一擴充顯示識 別資料覆蓋記憶體之第二擴充顯示識別資料），而先維持熱插拔 偵測訊號340在高準位，再將熱插拔偵測訊號340由高準位拉 低至低準位，再拉高至高準位，慑然如同一負脈波（pulse)。當 多電腦切換器30從電腦350切換至電腦352時，處理器300 維持熱插拔偵測訊號340為第一準位，本實施例中，係維持為 高準位，維持準位不變的目的在於針對支援螢幕熱插拔偵測之 電腦，當多電腦切換器30切換時，讓電腦350、352認為一直 都有與螢幕360耦接，否則在切換時電腦350、352會以為偵 16 200941288 測到螢幕360插拔或更換而重新讀取擴充顯示識別資料，造成 出畫時間延遲多達數秒。要特別說明的是，第一準位亦可低於 第二準位，其處理過程與上述類似。至於外部控制訊號，除了 由上述之鍵盤370能以熱鍵方式產生外，滑鼠、按鈕開關、有 線/無線搖控器、以及任何可適用於電腦350、352與多電腦切 換器30之週邊裝置（peripherals)等等，亦能用以使多電腦切換 器30手動更新記憶體310、312内擴充顯示識別資料，皆可作 為外部控制訊號的來源。 ❿ 需要注意的是，熱插拔偵測訊號340係可由低準位拉高至 高準位，再拉低至低準位。因此當處理器300比對出螢幕360 與記憶體310、312之擴充顯示識別資料不同時，先維持熱插 拔偵測訊號340在低準位，當記憶體310、312更新完成之後， 將熱插拔偵測訊號340由低準位拉高至高準位，再拉低至低準 位，儼然如同一正脈波（pulse)。當處理器300比對出螢幕360 與記憶體310、312之擴充顯示識別資料相同時，不需要更新 記憶體之擴充顯示識別資料（當然亦可直接以第一擴充顯示識 〇 別資料覆蓋記憶體之第二擴充顯示識別資料），而先維持熱插拔 偵測訊號340在低準位，再將熱插拔偵測訊號340由低準位拉 高至高準位，再拉低至低準位，慑然如同一正脈波（pulse)。當 多電腦切換器30從電腦350切換至電腦352時，處理器300 維持熱插拔偵測訊號340為低準位。 請參閱第4圖，係依據本發明可提供螢幕之擴充顯示識別 資料之方法流程圖。本發明之方法包括下列步驟： 步驟410，詢問螢幕之第一擴充顯示識別資料； 步驟420,將第一擴充顯示識別資料與儲存於至少一記憶 17 200941288 體之一第二擴充顯示識別資料予以比對； 步驟420-1，如步驟420之比對結果為是（相同），則不更新 第二擴充顯示識別資料，但傳送熱插拔偵測訊號至電腦；以及 步驟420-2,如步驟420之比對結果為否（不同），以第一擴 充顯示識別資料覆寫第二擴充顯示識別資料，並傳送一熱插拔 偵測訊號至電腦，使電腦自記憶體讀取第一擴充顯示識別資 料。另外，當有更換或插拔螢幕、執行熱鍵的情況，不管多電 腦切換器的擴充顯示識別資料有無進行更新時，處理器就會進 ® 行熱插拔偵測訊號的改變。又，當有更換或插拔螢幕、執行熱 鍵的情況，不管來自螢幕的擴充顯示識別資料有無改變時，處 理器可先以第一擴充顯示識別資料覆蓋第二擴充顯示識別資 料，而接續進行熱插拔偵測訊號的改變。 其中熱插拔偵測訊號為一高準位拉低至一低準位，再拉高 為高準位之訊號。或是一低準位拉高至一高準位，再拉低為低 準位之訊號。熱插拔偵測訊號之目的係針對支援螢幕熱插拔偵 測之電腦，使其偵測到螢幕有插拔或更換之現象，自動去讀取 © 儲存於記憶體内之擴充顯示識別資料。 本發明之主要優點包括：（a)多電腦切換器開機後會自動比 對螢幕與記憶體内之擴充顯示識別資料是否相同，不同時會以 螢幕之擴充顯示識別資料覆寫記憶體内之擴充顯示識別資料 (相同時亦可利用螢幕之擴充顯示識別資料覆寫記憶體内之擴 充顯示識別資料），使耦接至多電腦切換器之電腦能讀取到正確 之擴充顯示識別資料；（b)更換螢幕時，多電腦切換器會偵測到 螢幕有更換，自動更新記憶體内之擴充顯示識別資料；（c)能提 供使用者以熱鍵的方式，手動更新記憶體内之擴充顯示識別資 18 200941288 - 料；（d)熱插拔偵測訊號的控制方式，能解決支援螢幕熱插拔偵 測之電腦出晝延遲的問題。 綜上所述，本發明符合發明專利要件，爰依法提出專利申 請。惟以上所述者僅為本發明之較佳實施例，舉凡本發明所屬 技術領域中具有通常知識者，在爰依本發明精神架構下所做之 等效修飾或變化，皆應包含於以下之申請專利範圍内。 【圖式簡單說明】 第1A圖係依據本發明第一實施例的多電腦切換器應用之 ® 方塊圖； 第1B圖係處理器傳送至電腦之熱插拔偵測訊號波形圖； 第2A圖係依據本發明第二實施例的多電腦切換器應用之 方塊圖， 第2B圖係處理器傳送至電腦之熱插拔偵測訊號波形圖； 第3A圖係依據本發明第三實施例的多電腦切換器應用之 方塊圖； 第3B圖係處理器傳送至電腦之熱插拔偵測訊號波形圖； ❹ 以及 第4圖係依據本發明可提供螢幕之擴充顯示識別資料之方 法流程圖。 【主要元件符號說明】 10、20、30 多電腦切換器 100、200、300 處理器 110、112、210、212、310、312 記憶體 120、122、220、222、320、322 切換器 130、230、330 多工器 200941288 132、232、332 影像訊號介面切換器 140、240、340熱插拔偵測訊號 150、152、250、252 ' 350、352 電腦 160、260、360 螢幕 370 鍵盤In this embodiment, the first level is higher than the second level. Please also refer to the 2B 12 200941288 diagram, which is a waveform diagram of the hot plug detection signal 240 transmitted by the processor 200 to the computers 250 and 252. As can be seen from the figure, the hot plug detection signal 240 is pulled from the high level to the low level and then pulled high to the high level. Therefore, when the processor 200 compares the display 260 with the extended display identification data of the memory 210 and 212, the hot plug detection signal 240 is maintained at a high level, and after the memory 210, 212 is updated, the heat is applied. The plug detection signal 240 is pulled down from the high level to the low level, and then pulled up to the high level, as if it were the same negative pulse. When the processor 200 compares the screen 260 with the expanded display identification data of the memory 210, 212, it is not necessary to update the expanded display identification data of the memory (of course, the memory can be directly covered by the first extended display identification data. The second extension displays the identification data), and first maintains the hot plug detection signal 240 at a high level, and then pulls the hot plug detection signal 240 from the high level to the low level, and then pulls up to the high level. It is like the same negative pulse. When the KVM switch 20 is switched from the computer 250 to the computer 252, the processor 200 maintains the hot plug detection signal 240 as the first level. In this embodiment, the CPU maintains the high level and maintains the level unchanged. The purpose is to enable the computer 250, 252 to be connected to the screen 260 when the KVM switch 20 is switched, otherwise the KVM switch 20 is switched when the KVM switch 20 is switched. 250, 252 will detect the insertion or removal of the screen 260, and re-inquire and read the extended display identification data, causing the drawing time to be delayed by several seconds. It should be particularly noted that the first level can also be lower than the second level, and the processing procedure is similar to the above. It should be noted that the hot plug detection signal 240 can be pulled from the low level to the high level and then pulled down to the low level. Therefore, when the processor 200 compares the display 260 with the extended display identification data of the memory 210 and 212, the hot plug detection signal 240 is maintained at a low level. After the memory 210 and 212 are updated, 13 200941288 The hot plug detection signal 240 is pulled from the low level to the high level, and then pulled down to the low level, just like the same positive pulse. When the processor 200 compares the screen 260 with the expanded display identification data of the memory 210 and 212, it is not necessary to update the extended display identification data of the memory (of course, the first extended display identification data may be used to cover the memory. Secondly, the display identification data is expanded. First, the hot plug detection signal 240 is maintained at a low level, and then the hot plug detection signal 240 is pulled from the low level to the high level, and then pulled down to the low level. Such as the same positive pulse (pulse). When the KVM switch 20 is switched from the computer 250 to the computer 252, the processor 200 maintains the hot plug detection signal 240 at a low level. Referring to Fig. 3A, there is shown a block diagram of the application of the KVM switch 30 in accordance with the third embodiment of the present invention. The KVM switch 30 is coupled to the computers 350 and 352 to the screen 360, and the screen 360 has a first extended display identification data. The keyboard 370 is coupled to the KVM switch 30 for generating an external control signal to the KVM switch 30. The KVM switch 30 includes a processor 300, two memories 310, 312, two switches 320, 322, a multiplexer 330, and an image signal interface switch 332. The processor 300 is coupled to the screen 360 and the computer 350 and 352 for detecting the external control signal transmitted by the keyboard 370, receiving the first extended display identification data of the screen 360, and outputting a hot plug detection signal 340. To the computer 350, 352. The memory 310, 312 is coupled to the processor 300 through the multiplexer 330 for storing the second extended display identification data. The memories 310, 3 12 can be volatile memory or non-volatile memory. It should be noted that the memories 310 and 312 may also be directly coupled to the processor 300 without passing through the multiplexer 330. The function of the multiplexer 330 is to provide the processor 300 to write the first extended display identification data of the screen 360 into the memory 310, 312 by switching. The switch 320 can selectively couple the computer 350 to one of the screen 360 and the memory 310. The 200941288 is used to provide the first extended display identification data or the second extended display identification data of the computer 350. The switch 322 can selectively couple the computer 352 to one of the screen 360 and the memory 312 for providing the first extended display identification data or the second extended display identification data of the computer 352. In this embodiment, the KVM switch 30 can be switched to the computer 350, so the computer 350 reads the first or second extended display identification data from the memory 310 or the screen 360, and the computer 352 reads the second extension from the memory 312. Display identification data. The image signal interface switcher 332 is used to select one of the computer 350 and the computer 352 to transmit video and audio data to the screen 360, such as a digital image interface, a high definition multimedia interface, and a video graphics array interface. When the processor 300 detects an external control signal from the keyboard 370, the processor 300 compares whether the first extended display identification data and the second extended display identification data are the same; when the two are different, the processor 300 maintains hot swapping. The detection signal 340 is transmitted to the computer 350, 352 for a first level, and the first extended display identification data in the memory 310, 312 is overwritten by the multiplexer 330 with the first extended display identification data of the screen 360. After the memory 310, 312 stores the first extended identification data of the screen 360, the processor 300 converts the hot plug detection signal 340 from the first level to the second level, and then converts to the first level. The hot swap detection signal 340 of the two level conversions causes the computer 350 or 352 to detect that the screen 360 is turned off and on, or to detect the screen insertion or replacement, and to the KVM switch 30. The request for expanding the display identification data is sent, and the first extended display identification data is read from the memory 310, 312, so as to read the correct extended display identification data. When the processor 300 compares the first extended display identification data of the screen 360 with the second extended display identification data of the memory 310, 312, the processor 300 converts the hot plug detection signal 340 from the first level to the first level. The second level is converted to 15 200941288 - the first level. As described above, the hot swap detection signal 340 of the two level conversions causes the computer 350 or 352 to detect that the screen 360 is turned off and on. Alternatively, the screen 360 is inserted or removed, and the KVM switch 30 is requested to expand the display identification data. The first extended display of the screen 360 displays the identification data and the second extended display identification data of the memory 310, 312. The same is true, so the second extended display identification data of the memory 310, 312 is directly read, that is, the purpose of reading the screen 360 to correctly display the identification data is achieved. In this embodiment, the first level is higher than the second level. Please also refer to the 3B ® diagram, which is a waveform diagram of the hot plug detection signal 340 transmitted by the processor 300 to the computers 350 and 352. As can be seen from the figure, the hot plug detection signal 340 is pulled from the high level to the low level and then pulled high to the high level. Therefore, when the processor 300 is different from the extended display identification data of the screen 360 and the memory 310, 312, the hot plug detection signal 340 is maintained at a high level, and after the memory 310, 312 is updated, the heat is applied. The plug detection signal 340 is pulled from the high level to the low level and then pulled high to the high level, as if it were the same negative pulse. When the processor 300 compares the output of the screen 360 with the expanded display identification data of the memory 310 and 312, it is not necessary to update the extended display identification data of the memory (of course, the memory may be directly covered by the first extended display identification data. The second extension displays the identification data), and first maintains the hot plug detection signal 340 at a high level, and then pulls the hot plug detection signal 340 from the high level to the low level, and then pulls up to the high level. It is like the same negative pulse. When the KVM switch 30 is switched from the computer 350 to the computer 352, the processor 300 maintains the hot plug detection signal 340 as the first level. In this embodiment, the CPU maintains the high level and maintains the level unchanged. The purpose is to support the screen hot-swap detection computer. When the multi-computer switcher 30 switches, the computer 350, 352 thinks that it has always been coupled with the screen 360. Otherwise, the computer 350, 352 will think that when the switch is switched, 16 200941288 It is detected that the screen 360 is inserted or removed, and the extended display identification data is re-read, causing the drawing time to be delayed by several seconds. It should be particularly noted that the first level may also be lower than the second level, and the processing procedure is similar to the above. As for the external control signal, in addition to the above-mentioned keyboard 370 can be generated by hot keys, the mouse, the push button switch, the wired/wireless remote controller, and any peripheral device applicable to the computer 350, 352 and the KVM switch 30 Peripherals, etc., can also be used to enable the KVM switch 30 to manually update the display identification data in the memory 310, 312, which can be used as a source of external control signals. ❿ It should be noted that the hot plug detection signal 340 can be pulled from the low level to the high level and then pulled down to the low level. Therefore, when the processor 300 is different from the extended display identification data of the screen 360 and the memory 310, 312, the hot plug detection signal 340 is maintained at a low level, and after the memory 310, 312 is updated, the heat is applied. The plug detection signal 340 is pulled from the low level to the high level, and then pulled down to the low level, just like the same positive pulse. When the processor 300 compares the output of the screen 360 with the expanded display identification data of the memory 310 and 312, it is not necessary to update the extended display identification data of the memory (of course, the memory can be directly covered by the first extended display identification data). The second extension displays the identification data), and the hot plug detection signal 340 is maintained at the low level, and then the hot plug detection signal 340 is pulled from the low level to the high level, and then pulled down to the low level. , like the same positive pulse (pulse). When the KVM switch 30 is switched from the computer 350 to the computer 352, the processor 300 maintains the hot plug detection signal 340 at a low level. Referring to Fig. 4, a flow chart of a method for displaying display identification data by a screen according to the present invention is provided. The method of the present invention includes the following steps: Step 410: Query the first extended display identification data of the screen; Step 420, compare the first extended display identification data with the second extended display identification data stored in at least one memory 17 200941288 Step 420-1, if the result of the comparison in step 420 is (same), the second extended display identification data is not updated, but the hot plug detection signal is transmitted to the computer; and step 420-2, as in step 420 If the comparison result is no (different), the second extended display identification data is overwritten by the first extended display identification data, and a hot plug detection signal is transmitted to the computer, so that the computer reads the first extended display identification from the memory. data. In addition, when there is a replacement or plug-in screen and a hot key is executed, the processor will change the hot plug detection signal regardless of whether the extended display of the multi-computer switch indicates that the data is updated. Moreover, when there is a replacement or insertion or removal of the screen and the execution of the hot key, the processor may first overwrite the second extended display identification data with the first extended display identification data, regardless of whether the extended display identification data from the screen is changed or not. Hot swap detection signal changes. The hot plug detection signal is a high level low to a low level, and then pulled high to a high level signal. Or pull a low level to a high level, and then pull down the signal to the low level. The purpose of the hot plug detection signal is to support the screen hot plug detection computer to detect the insertion or removal of the screen, and automatically read the extended display identification data stored in the memory. The main advantages of the present invention include: (a) After the KVM switch is turned on, it automatically compares the screen display with the expanded display identification data in the memory, and at the same time, the display data is overwritten by the expansion of the screen to overwrite the expansion in the memory. Displaying the identification data (the same can be used to display the identification data in the memory to overwrite the extended display identification data in the memory), so that the computer coupled to the KVM switch can read the correct extended display identification data; (b) When the screen is replaced, the KVM switch detects that the screen has been replaced, and automatically updates the extended display identification data in the memory; (c) provides the user with the hot key to manually update the extended display identification in the memory. 18 200941288 - Material; (d) The hot-swap detection signal control method can solve the problem of delay in the computer that supports the hot-swap detection of the screen. In summary, the present invention complies with the requirements of the invention patent, and proposes a patent application according to law. The above is only the preferred embodiment of the present invention, and equivalent modifications or variations made by the present invention in accordance with the spirit of the present invention should be included in the following. Within the scope of the patent application. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1A is a block diagram of a KVM switch application according to a first embodiment of the present invention; FIG. 1B is a diagram of a hot plug detection signal transmitted from a processor to a computer; According to a block diagram of a KVM switch application according to a second embodiment of the present invention, FIG. 2B is a waveform diagram of a hot plug detection signal transmitted from a processor to a computer; FIG. 3A is a diagram according to a third embodiment of the present invention. Block diagram of the computer switcher application; Figure 3B is a diagram of the hot plug detection signal waveform transmitted by the processor to the computer; ❹ and Fig. 4 are flowcharts showing the method for displaying the identification information of the screen according to the present invention. [Main component symbol description] 10, 20, 30 KVM switch 100, 200, 300 processor 110, 112, 210, 212, 310, 312 memory 120, 122, 220, 222, 320, 322 switch 130, 230, 330 multiplexer 200941288 132, 232, 332 image signal interface switch 140, 240, 340 hot plug detection signal 150, 152, 250, 252 '350, 352 computer 160, 260, 360 screen 370 keyboard
2020