BIOS-Check will check your system's BIOS to see if it is properly controlling all IDE hard drives in your system. The program must be run from it's own self-booting diskette. When you double-click the BIOS-Check entry in your cover CD-ROM browser program, the routine to create this diskette will start, and you will be prompted to insert a blank floppy disk for the purpose.
When you restart, booting from the floppy disk, BIOS-Check will automatically run and check your system. BIOS-Check obtains information about your IDE drives from three sources:
1. Direct from the drive with the ATA Drive ID command.
2. From the BIOS via the legacy Function 8 of Interrupt 13h, which gives the logical Cylinder, Head and Sector counts for the drive. This legacy function is limited to reporting 8.4Gb as the maximum drive capacity, which would be 1024 cylinders, 255 heads, and 63 sectors per track.
3. From the BIOS via the extended Function 48h (if supported) of Interrupt 13h, which gives the total sector count for the drive regardless of it's size.
BIOS's which support Function 48h also support reading and writing of drives over 8.4Gb in capacity. These are said to be Extended BIOS Functions. BIOS's which do not support these Extended Functions cannot access drives over 8.4Gb.
DOS 6.22 or earlier cannot utilise the Extended BIOS functions for accessing hard drives and is therefore limited to using drives 8.4Gb or less in capacity (whether your BIOS supports the Extended Functions or not). Windows 95/98/NT utilises these functions and can therefore access drives over 8.4 GB, but only if the BIOS supports the Extended Functions.
When performing the BIOS check, the program first checks to see that the BIOS drive capacity is close to the actual IDE drive capacity. BIOS-Check then calls the BIOS to read a sector from every 100th cylinder and checks the drives ATA registers to insure that the BIOS did read the correct sector. Sometimes an IDE drive may not be controlled by the BIOS at all. In this case the "BIOS Drive" column will show "N/A" and the BIOS capacities will be zero. If this occurs, make sure your BIOS is set up to auto detect the drive. With older BIOS's you may need to manually enter the drive's Cylinder, Head, and Sector counts, but BIOS's that old usually won't handle today's larger drives anyway.
Sometimes a non-IDE drive, such as SCSI, will have Interrupt 13h support via the adapters own ROM BIOS. In this case the "IDE Drive" column will show "N/A" and the "Real IDE Capacity" column will show "Unknown".
BIOS-Check only checks IDE drives on the Primary or Secondary IDE Channel. It will not check SCSI drives or IDE drives attached to add-in cards like Promise Technologies Ultra 33 and Ultra 66 cards. A new version is in the works that supports these add-in cards. The latest version of EZ-Drive supports both of these Promise Technologies cards.
If you received setup software with your drive, such as EZ-Drive by StorageSoft, it is highly recommended that you use it to set up your drive, even if your BIOS properly supports your new drive. EZ-Drive will not install the EZ-BIOS drive handler on your boot drive if your system BIOS is properly handling all of your IDE drives.
Some BIOS's will hang during the boot process if a large drive is attached to an IDE channel. To overcome this problem many drive manufacturers have special jumper settings on the drive that make the drive "look" smaller to the BIOS. EZ-Drive can detect when such a special jumper setting is used and can install the EZ-BIOS drive handler to access the real capacity of the drive. BIOS-Check can detect when the special jumper setting is used and, when it is, can determine whether the BIOS recognises the actual drive size.
