Hitachi DK23DA-30F Owners Manual - Page 94

Word 255 Table 6.19 Device Configuration Set Command Data Structure (Continued) Description Integrity word bit 15 - 8 Checksum The checksum shall be the two's complement of the sum of all byte in words 0 through 254 and the byte consisting of bits 7:0 of word 255. Each byte shall be added with unsigned arithmetic, and overflow shall be ignored. The sum of all bytes is zero when the checksum is correct bit 7 - 0 Signature Code Bits 7:0 of this word shall contain the value A5h. Error Outputs: If DEVICE CONFIGURATION FREEZE LOCK is set or If any of the bit modification restrictions described are violated, the device returns command aborted. Registers Cylinder High Cylinder Low Device/Head Sector Number Sector Count 76543210 Word Location Number Bit Location Number bit15 - 8 - X - DRV XX Bit Location Number bit 7 - 0 XX (Vendor Unique) Sector Count Register: This register contains vendor unique value by the device. Cylinder Low Register, Sector Number: If the command was aborted because an attempt was made to modify a mode or feature that cannot be modified with the device in its current state, these registers contain bits (15:0) set in the bit positions that correspond to the bits in the device configuration overlay data structure words 1, 2, or 7 for each mode or feature that cannot be changed. If not, the value is 00h. Cylinder High Register: If the command was aborted because an attempt was made to modify a bit that cannot be modified with the device in its current state, this register contains the offset of the word that cannot be changed. If not, the value is 00h. K6602705 Rev.3 08.20.01 - 94 -