when used to Adsl board This object contains the second 128 downstream sub-carrier bit allocations (sub-carrier # 129-256). This object is 64 bytes in length, where each byte contains 2 sub-carrier values. Byte 1 - 64 Downstream bit allocation (second 128 sub-carriers), one byte for two sub-carriers. 1 Bits 4 - 7 # bits in 129th downstream sub-carrier 1 Bits 0 - 3 # bits in 130th downstream sub-carrier ... 64 Bits 4 - 7 # bits in 255th downstream sub-carrier 64 Bits 0 - 3 # bits in 256th downstream sub-carrier when used to Adsl2+ board This object contains the second 256 downstream sub-carrier bit allocations (sub-carrier # 257-512). This object is 256 bytes in length, where each byte contains 1 sub-carrier values. Byte 1 - 256 Downstream bit allocation (second 256 sub-carriers), one byte for one sub-carriers. 1 Bits 0 - 7 # bits in 1st downstream sub-carrier ... 255 Bits 0 - 7 # bits in 255th downstream sub-carrier 256 Bits 0 - 7 # bits in 256th downstream sub-carrier