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usb2comport [2009/09/02 06:53]
twdorris
usb2comport [2024/03/15 11:16]
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-====== USB to COM Port Mapping ====== 
-===== The Problem ===== 
-When connecting our ECMLink cable to the laptop, the FTDI driver used by our cable wants to assign different COM ports to each cable. ​ This is not practical for a laptop used by a shop or general tuner when connecting cables from multiple customer cars. 
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-To correct this, you can tell the FTDI driver to use a fixed COM port for each physical USB port on your laptop. 
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-===== The Solution ===== 
-To tell the FTDI driver to always assign the same COM port to a physical USB port, you have to edit the following registry key: 
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-''​HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\FTDIBUS\Parameters\LocIds''​ 
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-In this key, you will specify the location IDs of each USB port you plan to use. 
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-To obtain the location IDs of your physical USB ports, use the [[http://​www.ecmtuning.com/​images/​forums/​usbview/​usbview.exe|USBView application]]. ​ When you run this application,​ you will be presented with a screen as shown below. ​ Of course, the laptop on which you are running this application will have a different configuration.  ​ 
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-{{  http://​www.ecmtuning.com/​images/​forums/​usbview/​usbview-01.gif ​ }} 
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-First, select the Options->​Location IDs menu item and then hit F5 to refresh the screen. ​ The above screen will now look like the one shown below. 
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-Notice that the **Port** numbers from the first screen are now shown as **Loc** numbers. ​ Those are the physical location IDs of the USB ports on your PC. 
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-{{  http://​www.ecmtuning.com/​images/​forums/​usbview/​usbview-02.gif ​ }} 
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-To determine the location ID that corresponds to a physical USB port on your laptop, simply insert one of our ECMLink cables into the port.  Once you have inserted this cable, hit F5 again to refresh USBView. 
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-Now you will see something like the following (notice the new **USB Serial Converter** at **Loc41**). 
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-{{  http://​www.ecmtuning.com/​images/​forums/​usbview/​usbview-03.gif ​ }} 
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-Note that **Loc41** now says ''​DeviceConnected : USB Serial Converter''​ where as before it simply said ''​NoDeviceConnected''​. ​ That means that the USB port into which our cable was inserted is at location ID ''​0x00000041''​. ​ When this cable is removed from that port and installed into another port, ''​Loc42''​ (in this example) shows ''​DeviceConnected'',​ indicating the following. 
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-''​PORT A – Location ID 0x00000041''​ 
-''​PORT B – Location ID 0x00000042''​ 
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-Identify these two ports on your local machine and write them down.  The following examples will use these two ports. ​ Be sure to use your OWN IDs instead of the ones used in this example as your PC will be different 
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usb2comport.txt · Last modified: 2024/03/15 11:16 (external edit)