## Physical Device Driver Reference

[prev][next][parent][TOC]

### Category 80h OEMHLP IOCtls

The OEMHLP interface was originally designed to allow Original Equipment Manufacturers (OEMs) to modify and adapt the OS/2 operating system to run on their hardware. In the past, IBM supported the OS/2 operating system on IBM hardware only. Therefore, OEMs had to build modified versions of the OS/2 operating system. The OEMHLP interface facilitated this process.

IBM currently tests the OS/2 operating system on a wide variety of OEM hardware. It is no longer necessary for OEMs to adapt the OS/2 operating system to their machines. Now the OEMHLP interface can be used to obtain real-mode information. This information can be passed to applications and device drivers running in protect mode. Applications and physical device drivers running in protect mode cannot access BIOS through the INT interface. The OEMHLP interface allows access to BIOS information and functions that are essential to these programs.

For example, you might want to issue INT 15h calls from your device driver initialization code to determine if an Extended Industry Standard Architecture (EISA) adapter is present. The following examples show the methods to determine if a specific EISA or Micro Channel adapter is present .