HP FlexBuild Feature Byte

The Feature Byte is HP's lingo for a set of 2-digit values, used to list the configuration of the system filled in the factory that specify software and hardware features.

HP/Compaq PCs with preloaded images using FlexBuild 1.x and 2.x will have these stored as detailed values in the SMBIOS Type 11 OEM strings table, not as a set of 2-digit values.

## CRC

CRC table in hex`: 0x00, 0x1B, 0x36, 0x2D, 0x6C, 0x77, 0x5A, 0x41, 0xD8, 0xC3, 0xEE, 0xF5, 0xB4, 0xAF, 0x82, 0x99, 0xD3, 0xC8, 0xE5, 0xFE, 0xBF, 0xA4, 0x89, 0x92, 0x0B, 0x10, 0x3D, 0x26, 0x67, 0x7C, 0x51, 0x4A, 0xC5, 0xDE, 0xF3, 0xE8, 0xA9, 0xB2, 0x9F, 0x84, 0x1D, 0x06, 0x2B, 0x30, 0x71, 0x6A, 0x47, 0x5C, 0x16, 0x0D, 0x20, 0x3B, 0x7A, 0x61, 0x4C, 0x57, 0xCE, 0xD5, 0xF8, 0xE3, 0xA2, 0xB9, 0x94, 0x8F, 0xE9, 0xF2, 0xDF, 0xC4, 0x85, 0x9E, 0xB3, 0xA8, 0x31, 0x2A, 0x07, 0x1C, 0x5D, 0x46, 0x6B, 0x70, 0x3A, 0x21, 0x0C, 0x17, 0x56, 0x4D, 0x60, 0x7B, 0xE2, 0xF9, 0xD4, 0xCF, 0x8E, 0x95, 0xB8, 0xA3, 0x2C, 0x37, 0x1A, 0x01, 0x40, 0x5B, 0x76, 0x6D, 0xF4, 0xEF, 0xC2, 0xD9, 0x98, 0x83, 0xAE, 0xB5, 0xFF, 0xE4, 0xC9, 0xD2, 0x93, 0x88, 0xA5, 0xBE, 0x27, 0x3C, 0x11, 0x0A, 0x4B, 0x50, 0x7D, 0x66, 0xB1, 0xAA, 0x87, 0x9C, 0xDD, 0xC6, 0xEB, 0xF0, 0x69, 0x72, 0x5F, 0x44, 0x05, 0x1E, 0x33, 0x28, 0x62, 0x79, 0x54, 0x4F, 0x0E, 0x15, 0x38, 0x23, 0xBA, 0xA1, 0x8C, 0x97, 0xD6, 0xCD, 0xE0, 0xFB, 0x74, 0x6F, 0x42, 0x59, 0x18, 0x03, 0x2E, 0x35, 0xAC, 0xB7, 0x9A, 0x81, 0xC0, 0xDB, 0xF6, 0xED, 0xA7, 0xBC, 0x91, 0x8A, 0xCB, 0xD0, 0xFD, 0xE6, 0x7F, 0x64, 0x49, 0x52, 0x13, 0x08, 0x25, 0x3E, 0x58, 0x43, 0x6E, 0x75, 0x34, 0x2F, 0x02, 0x19, 0x80, 0x9B, 0xB6, 0xAD, 0xEC, 0xF7, 0xDA, 0xC1, 0x8B, 0x90, 0xBD, 0xA6, 0xE7, 0xFC, 0xD1, 0xCA, 0x53, 0x48, 0x65, 0x7E, 0x3F, 0x24, 0x09, 0x12, 0x9D, 0x86, 0xAB, 0xB0, 0xF1, 0xEA, 0xC7, 0xDC, 0x45, 0x5E, 0x73, 0x68, 0x29, 0x32, 0x1F, 0x04, 0x4E, 0x55, 0x78, 0x63, 0x22, 0x39, 0x14, 0x0F, 0x96, 0x8D, 0xA0, 0xBB, 0xFA, 0xE1, 0xCC, 0xD7`

The encoding of such CRC is done as follows:

* For the first digit's value, lookup its value in the CRC table using the current value (defaults to 0 for the first occurence) for each character. XOR this with the character to get the new CRC value. Store this in a temporary value which will be set as value.
* The same steps apply to the second digit, but with the lookup done in reverse order.
* Use the digit values to index into the CRC digit map ("`ABDEFGHMNQRTYadefghmnqrty2345789`") and get the respective CRC character.

## Legacy Feature Byte

HP/Compaq systems with preloaded images using FlexBuild 1.x will not only have feature bytes stored in Type 11, but also in the SMBIOS Type 1 System Information's Version string, of which the first 7 digits and last 2 digits represent Legacy Feature Byte. (e.g.: from 0nx1411RE101DIABL10, the Legacy Feature Byte is 0nx141110).

The first 3 digits are encoded using a special base-89 encoding with the character map "`0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ!#$&'()*+,-./:;=?@[\\]^_`{}~`". The decode is done by multiplying the output by the length of the character map (89) and adding the position of the digit in the character map (e.g. n is located at the 24th character, meaning n = 23).

When decoded, the first three bytes of the decoded LFB are the decoded 3 digits written in big-endian order. The last 6 digits are subtracted by 48 to become integer values. (e.g.: 0nx141110 decoded in hex form is: `0x00, 0x08, 0x20, 0x01, 0x04, 0x01, 0x01, 0x01, 0x00`). The decoded values are also encoded in bit form, of which the second digit indicates support for 5.1 sound, Corel preload, MS Word preload, WEM, Hi-Imaging preload and 5.1 speaker bundle and the third indicates support for DVD and CD-RW drive(s), VE, TV app, analog audio, DVD+RW drive (if present), WKSDVD and ET as 1 bit booleans, while remaining digits tell if the TV card uses PAL or NTSC input (if present), branding type, CPU fan check, AC power fail-safe (1st bit means none, 2nd means presence, 3rd means automatic) and floppy drive presence. (e.g. 0nx141110 tells that the system presents a floppy drive and a DVD+RW drive, TV card uses NTSC input, system has no AC power fail-safe, uses the Compaq Presario branding and was WEM preload).