Medium Access Control (MAC) and Physical Layer (PHY) - CISE

4-June-07 P1901_PRO_016_r0
i) CRC: CRC-32-IEEE 802.3 calculation. The complete ABLP_inf data is used, considering as 0 the CRC
field.
j) Tonemap Format: information about the format used in the Tonemap field.
k) Tonemap: tonemap data. Tonemap data field shall be in the format set in Tonemap Format field.
l) CS Format: information about the format used in the CS field.
m) CS: cycle selection data. CS field shall be in the format set in the CS Format field.
9.1.2.3.1 Tonemap format details
Tonemap basic format is defined here. This format shall be used when Tonemap Format field value is set to 1
(0x0001). Format description:
- Tonemap sets the value for 1536 subcarriers.
- Every subcarrier uses 4 bits to describe subcarrier bit-loading value.
- Tonemap field length is 768 octects.
- The first octet contains the first subcarrier (lowest frequency subcarrier) bit-loading value in the least
significant bits and the second subcarrier bit-loading value in the more significant bits.
- The second octet contains the third and fourth subcarrier bit-loading values; the third octet contains the fifth
and sixth values, and so on.
9.1.2.3.2 Cycle Selection details
CS basic format is defined here. This format shall be used when CS Format field first octet is set to 1 (0x01). CS
Format field second octet represents the number of octet pairs in the CS field. See Figure 72.
Figure 72: CS Format field
Therefore, CS field length is two times the Zone Count value. Each two octets define a part of the cycle when the
tonemap can be used. The first octet represents the start and the second octet stands for the end (both included).
Start and end values shall be defined by a synchronized Q value (see 4.3.11).
Submission page 195 UPA-OPERA