beautypg.com

Special per-channel register operation – Rainbow Electronics DS21458 User Manual

Page 46

background image

DS21455/DS21458 Quad T1/E1/J1 Transceivers

46 of 270

7. SPECIAL PER-CHANNEL REGISTER OPERATION

Some of the features described in the data sheet that operate on a per-channel basis use a special method
for channel selection. The registers involved are the per-channel pointer registers (PCPR) and per-channel
data registers 1 to 4 (PCDR1–4). The user selects the function(s) that are to be applied on a per-channel
basis by setting the appropriate bit(s) in the PCPR register. The user then writes to the PCDR registers to
select the channels for that function. The following is an example of mapping the transmit and receive
BERT function to channels 9, 10, 11, 12, 20, and 21:


Write 11h to PCPR
Write 00h to PCDR1
Write 0fh to PCDR2
Write 18h to PCDR3
Write 00h to PCDR4


More information about how to use these per-channel features can be found in their respective sections in
the data sheet.


Register Name:

PCPR

Register Description:

Per-Channel Pointer Register

Register Address:

28h


Bit

# 7 6 5 4 3 2 1 0

Name RSAOICS

RSRCS

RFCS BRCS

THSCS

PEICS TFCS BTCS

Default 0 0 0 0 0 0 0 0


Bit 0/BERT Transmit Channel Select (BTCS).

Bit 1/Transmit Fractional Channel Select (TFCS).

Bit 2/Payload Error Insert Channel Select (PEICS).

Bit 3/Transmit Hardware Signaling Channel Select (THSCS).

Bit 4/BERT Receive Channel Select (BRCS).

Bit 5/Receive Fractional Channel Select (RFCS).

Bit 6/Receive Signaling Reinsertion Channel Select (RSRCS).

Bit 7/Receive Signaling All Ones Insertion Channel Select (RSAOICS).