S (4 bit field)
S is a parameter used for calculation of the minimum number of slots between two successive Channel request messages. The field is coded according to the following table:

bit
4 3 2 1
0 0 0 0 S = 12
0 0 0 1 S = 15
0 0 1 0 S = 20
0 0 1 1 S = 30
0 1 0 0 S = 41
0 1 0 1 S = 55
0 1 1 0 S = 76
0 1 1 1 S = 109
1 0 0 0 S = 163
1 0 0 1 S = 217
All other values reserved.

MAX_RETRANS (2 bit field for each Radio Priority 1..4)
Indicates for each Radio Priority level 1 to 4 the maximum number of retransmissions allowed. Radio Priority 1 represents the highest priority. The field is coded with two bits per Radio Priority level according to the following table where the first two bits refer to Radio Priority 1, the second two bits to Radio Priority 2, etc.:

bit
2 1
0 0 1 retransmission allowed
0 1 2 retransmissions allowed
1 0 4 retransmissions allowed
1 1 7 retransmissions allowed

PERSISTENCE_LEVEL (4 bit field for each Radio Priority 1..4)
The PERISTENCE_LEVEL field indicates the values of the access persistence level P(i) for each Radio Priority i (i = 1..4) where Radio Priority 1 represents the highest Radio Priority of an LLC PDU to be transmitted.

bits
4 3 2 1
0 0 0 0 persistence level 0
0 0 0 1 persistence level 1
0 0 1 0 persistence level 2
0 0 1 1 persistence level 3
0 1 0 0 persistence level 4
: : :
1 1 1 0 persistence level 14
1 1 1 1 persistence level 16

ACC_CONTR_CLASS ( 16 bit field)
Access Control Class N (bit 1-16) (see octet 3 and 4 of the RACH Control Parameters IE in 3GPP TS 44.018) . For a mobile station with Access Control Class =N access is not barred if the Access Control Class N bit is coded with a ‘0’; N = 0, 1,….9, 11,…,15. Bit 11= the EC bit is the Emergency Call Allowed coded as specified in 3GPP TS 44.018.