| Parent |
| NOTE: | This web site is not some kind of 'official' documentation hub for the XT-IDE card. It is simply the result of someone who decided to add to the documentation that exists elsewhere. |
| • | Looks for the XTIDE Universal BIOS (XUB) in memory space. | |
| • | Identifies the motherboard class (PC/XT/AT). | |
| • | Attempts to identify the motherboard BIOS. | |
| • | Looks for and reports on certain problems. |
| • | Warn-then-exit if the motherboard BIOS (if identified) is known not to support BIOS expansion ROM's. (Usually, 1981 and 1982 dated motherboard BIOS'.) |
| • | Warn-then-exit if unable to find the XUB in memory space. |
| • | Warn-then-exit if the XUB is found at multiple locations in memory space. |
| • | Warn-then-exit if the XUB is found in segment 'A' or segment 'B'. |
| (Segments A and B are reserved for video RAM. Any BIOS expansion ROM code [e.g. XUB] placed there will not be found by the motherboard BIOS.) | |
| • | If the XUB is found in segment 'F' - Warn-then-exit if the computer is an IBM 5150, 5160, or 5170. - Warn (but do not exit) if not an IBM 5150, 5160, or 5170. |
| • | Warn (but do not exit) if the XUB is found in conventional memory. |
| (No exit is done because perhaps the XUB was placed there via 'optromloader' software.) | |
| • | Warn-then-exit if the XUB is at an address that is not a multiple of 2 KB, e.g. D0400. |
| (The motherboard BIOS searches for BIOS expansion ROM code in increments of 2 KB.) | |
| • | Warn (but do not exit) if the XUB is at an address that is not a multiple of 8 KB. |
| (That is unusual because the ROM address switches/jumpers on XT-IDE cards set an address that is a multiple of 8 KB, however, maybe the XUB is somewhere other than on the XT-IDE card.) | |
| • | Warn-then-exit if the declared size (third byte of BIOS expansion ROM) is zero. |
| • | Warn-then-exit if the declared size (third byte of BIOS expansion ROM) is not a multiple of 2 KB. |
| • | Warn-then-exit if the declared size (third byte of BIOS expansion ROM) is less than 4 KB. |
| • | Warn-then-exit if the declared size (third byte of BIOS expansion ROM) is greater than 32 KB. |
| • | Warn-then-exit if the 8-bit checksum of the declared size is not 00. |
| • | Warn-then-exit if the AT version of the XUB is on a PC or XT class computer. |
| • | Warn-then-exit if the string "XTIDE Universal" is in the header of a segment, but the first two bytes of the segment are not AAh and 55h. (Indicating a particular case of corrupted ROM contents.) |
| • | If an IBM 5170 motherboard BIOS detected, and it is dated 01/10/84, warn of possible 01/10/84 BIOS incompatibility with the XUB. (See note 1 at the bottom of here). |
| • | If an IBM 5170 motherboard BIOS detected, and the XUB found at E0000 (i.e. in sockets U17/U37 of IBM 5170 motherboard), warn-then-exit if the 8-bit checksum of segment 'E' is not 00. |
| • | It cannot detect if the XUB is misconfigured for your particular situation. For example, having the device type in the XUB inappropriately set for your particular make-model of XT-IDE/XT-CF card. For example, having the 'base I/O address' in the XUB set to something that does not match the base I/O address that your XT-IDE/XT-CF card is set to. |
| • | It does not look for the 'IDE interface' (the I/O ports) part of the XT-IDE/XT-CF card. |
| • | It cannot identify a resource conflict. For example, in the IBM 5170, segment 'E' (E0000 to EFFFF) is decoded by the motherboard for motherboard hosted ROM, and therfore, configuring the XT-IDE/XT-CF card to a start its ROM at address E0000 (or above) would be a conflict (in this case, resulting in bus contention on the data bus). |
