can you stop Windows polling the serial ports at boot up?

[Basil]

I have some devices (solid state relays controlling large power supplies) running off the true serial ports on my motherboard. I use this set up to remotely switch the supplies on or off via remote desktop using a simple DOS program. However, on boot up Windows 7 64 bit seems to "poll" the ports sending outputs momentarily high a few times. The SSD's, the big linear power supplies and I don't like this! Can it be stopped? Thanks.

 

[samuria]

Is it windows or the bios normally the bios will do it as it needs to know whats on the system

 

[Basil]

Is it windows or the bios normally the bios will do it as it needs to know whats on the system

Hmm, good question, I don't know the answer. On another forum someone just sent me this link, which initially sounded hopeful, but you have me wondering now... I don't suppose it can be "turned off" in the BIOS, can it?


serial - Windows 7 PC - disable sending data to com ports at bootup - Super User

 

[iko22]

Turning off in BIOS will disable the serial ports altogether. This is a not very good solution if you have serial port devices attached!! You want to disable something that still permits the use of the comms ports, when controlling the relays. The problem appears to be that Windows tries to detect the presence of a serial mouse, upon Windows booting.

One solution would be to have the serial port devices (relays) turned off during Windows 7 boot-up, and have these devices enabled when Windows had finished booting. That could mean editing the software for the comms port on the relays.

Another solution would be to get the relay device to recognise the windows command, and flush it out, like not act on it.

Alternatively, you could just disable the detection of the serial mouse at boot tme. There is not much documentation around on how to do this. In Windows XP, you would modify the boot.ini file. But with later versions of Windows, there is no Boot.ini file to edit! The solution appears to be to edit the registry. The side effect of this modification would be that your computer would be unable to communicate with a serial mouse - if you have a USB mouse, that should not impact your system too much.

Here is some documentation on how to disable the detection of the serial mouse at boot time on windows 7, which I found at TALtech instruments : Disabling Windows detection of Serial Mice (including Windows 7)