Maxim Integrated 73M1822/73M1922 Implementers Guide - Manual (Page 11)

UG_1x22_052 73M1822/73M1922 Implementer’s Guide
Rev. 1.0 11
3.2.2 Initial Line State Configuration
The default condition of the device is to be on hook after reset and startup.
The registers used in this procedure are:
0x05 ENGPIO7 ENGPIO6 ENGPIO5 ENGPIO4 ENAPOL ENDET ENSYNL ENRGDT
Write X X X X 1 X 1 X
0x12 OFH ENDC ENAC ENSHL ENLVD ENFEL ENDT ENNOM
Write 0 0 0 0 0 1 0 0
0x13 DCIV1 DCIV0 ILM RSVD PLDM OVDTH IDISPD1 IDISP0
Write VAL1[1:0] 0 0 0 0 0 0
0x14 TXBST DAA1 DAA0 Res RXBST RLPNH RXG1 RXG0
Write X X X 0 X X X X
0x15 RSVD DISNTR Res CIDM THEN ENUVD ENOVD ENOID
Write 0 0 0 0 1 0 0 0
0x16 TXEN RXEN RLPNEN ATEN FSCTR3 FSCTR2 FSCTR1 FSCTR0
Write 1 1 0 1 VAL3[3:0]
0x17 APWS Res Res ACZ1 ACZ0 Res Res Res
Write 0 0 0 VAL2[1:0] 0 0 0
The temporary variables defined in this procedure are:
VAL1 = Set the DCIV bits to the desired DC current voltage characteristic as defined in the Data Sheet.
VAL2 = System appropriate value for ACZ[1:0].
VAL3 = System appropriate value for FSCTR[3:0].
Begin
1. Set ENAPOL =1 and ENSYNL = 1, to allow automatic polling of line side registers (write RG05 =
xxxx_1x1x).
2. Set ENFEL = 1, OFH = ENDC = ENAC = ENSHL = ENVLD = ENDT = ENNOM = 0 (Write RG12 =
0x40).
3. Set ILM = RSVD = PLDM = OVDTH = IDISPD = Res = 0, DCIV = VAL1 (Write RG13 =
Val1[1:0]00_0000).
4. Write RG14 = xxx0_xxxx
5. Set THEN = 1, set ENOLD = DISNTR = CHPSEN = CIDM = ENUVD = ENOVD = ENOID = 0 (Write
RG15 = 0000_1000)
6. Set TXEN = RXEN = ATEN = 1, RLPNEN = 0 and FSCTR[3:0] =VAL3[3:0] (Write RG16 =
1101_VAL3[3:0]).
7. Set RG17[4:3] = VAL2 (write RG17 = 0x000_VAL2_000).
End
After this point the host may selectively enable other on hook operations such as ring detection or CID
mode.