3 hdlc mapping – Maxim Integrated DS21Q55 User Manual
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22.3 HDLC Mapping
22.3.1 Receive
The HDLC controllers need to be assigned a space in the T1/E1 bandwidth in which they will transmit
and receive data. The controllers can be mapped to either the FDL (T1), Sa bits (E1), or to channels. If
mapped to channels, then any channel or combination of channels, contiguous or not, can be assigned to
an HDLC controller. When assigned to a channel(s) any combination of bits within the channel(s) can be
avoided.
The HxRCS1–HxRCS4 registers are used to assign the receive controllers to channels 1–24 (T1) or
1–32 (E1) according to the following table.
REGISTER
CHANNELS
HxRCS1
1–8
HxRCS2
9–16
HxRCS3
17–24
HxRCS4
25–32
Register Name:
H1RCS1, H1RCS2, H1RCS3, H1RCS4
H2RCS1, H2RCS2, H2RCS3, H2RCS4
Register Description:
HDLC # 1 Receive Channel Select x
HDLC # 2 Receive Channel Select x
Register Address:
92h, 93h, 94h, 95h
A2h, A3h, A4h, A5h
Bit #
7
6
5
4
3
2
1
0
Name
RHCS7
RHCS6
RHCS5
RHCS4
RHCS3
RHCS2
RHCS1
RHCS0
Default
0
0
0
0
0
0
0
0
Bit 0/Receive HDLC Channel Select Bit 0 (RHCS0). Select Channel 1, 9, 17, or 25.
Bit 1/Receive HDLC Channel Select Bit 1 (RHCS1). Select Channel 2, 10, 18, or 26.
Bit 2/Receive HDLC Channel Select Bit 2 (RHCS2). Select Channel 3, 11, 19, or 27.
Bit 3/Receive HDLC Channel Select Bit 3 (RHCS3). Select Channel 4, 12, 20, or 28.
Bit 4/Receive HDLC Channel Select Bit 4 (RHCS4). Select Channel 5, 13, 21, or 29.
Bit 5/Receive HDLC Channel Select Bit 5 (RHCS5). Select Channel 6, 14, 22, or 30.
Bit 6/Receive HDLC Channel Select Bit 6 (RHCS6). Select Channel 7, 15, 23, or 31.
Bit 7/Receive HDLC Channel Select Bit 7 (RHCS7). Select Channel 8, 16, 24, or 32.