Changing the size of the font when printing from the port

Hi, I'm trying to change the size of the font when i send the information to the printer, my code is:

Code:

Open Puerto For Output As #fNum 

    If Err = 0 Then        
        Print #fNum, strCadena
        If bClosePortAfterPrint Then Close #fNum        
    End If

where "Puerto" is the printer port, (LPT1, mapped to a network printer), and what i'm looking for is for a common command to tell the printer to make the font condensed.

I won't use the printer object, because it is to slow, even i know that with that object i can use Printer.fontSize=10, or something like that. Printing from the port is fast, and for my application, i need to print fast, so, if you know if exists a common command to tell every printer (there will be 44 dot-matrix printers, and maybe differents) or if there is another way to print fast and changing the size of the font, please let me know

Thanks in advance