The Internal Leading control contains a value that specifies an amount of space
reserved in each character cell for accent characters and so on. For most 9- and
24-pin printers, this value should be 0. (The point size specified by most applications is the sum of the PixHeight and Internal Leading values.)
Note:
Some of the PFM files supplied with the Microsoft Windows Device Driver Kit reflect values that are compatible with earlier versions of Windows-based printer drivers. For example, Epson and IBM printers have values that are not listed here. However, for recently created drivers, font metric values should reflect how the printer produces device fonts.
For the Diconix 150 Plus printer, this value is 0. The device fonts for the Diconix do not support internal leading.