I need to access an IO Port of my motherboard to drive a Cash Drawer connected to it. It is a custom mother board with Intel Core I5 processor. Target OS - Windows XP
The IO port I need to access is marked as a “Motherboard Resource” in Windows device manager. Hence a resource conflict occurs when my IO port driver is installed.
It is possible to install the driver without specifying any address range in the INF file (i.e by commeting the line IOConfig=4B8-4B8) and operate as intended.
In this configuration, the driver does not indicate it requires any resource. But regardless of that, the values are written to the ports. (this works).
Is there a better solution to resolve the conflict other than not specifying the required resources during install time and accessing the port even though they are flagged as motherboard resources ?
It should be OK, as long as the system configuration is entirely under your control.
It would only be not advisable, if the device is shipped for general availability to work in arbitrary systems.
I had a similar issue with Windows 7 Embedded 32 Bit and some PC-104
adapters, they only had 10 bit address line decoding.
My solution was for a dedicated medical instrument application where we
completely controlled the system configuration.
I changed the address decoding option to (ffff:
and that removed the
conflict with the motherboard resources.
IOConfig=4B8-4B8)(ffff:
If your custom motherboard is or can be modified to use 16 bit address
decoding this is a perfectly valid change to the INF file.
If you have less then 16 bit address decoding for your device it may appear
at several other alias address spaces in the processors IO address space.
Hence you will need to test this change in your enviroment to know for sure
that your device is not sharing some other devices IO range.
Phil
wrote in message news:xxxxx@ntdev…
>I need to access an IO Port of my motherboard to drive a Cash Drawer
>connected to it. It is a custom mother board with Intel Core I5 processor.
>Target OS - Windows XP
>
> The IO port I need to access is marked as a “Motherboard Resource” in
> Windows device manager. Hence a resource conflict occurs when my IO port
> driver is installed.
>
> It is possible to install the driver without specifying any address range
> in the INF file (i.e by commeting the line IOConfig=4B8-4B8) and operate
> as intended.
>
> In this configuration, the driver does not indicate it requires any
> resource. But regardless of that, the values are written to the ports.
> (this works).
>
> Is there a better solution to resolve the conflict other than not
> specifying the required resources during install time and accessing the
> port even though they are flagged as motherboard resources ?
>
>