DS2152
8.1.2 Per-Channel Code Insertion
The second method involves using the Transmit Channel Control Registers (TCC1/2/3) to determine
which of the 24 T1 channels should be overwritten with the code placed in the Transmit Channel
Registers (TC1 to TC24). This method is more flexible than the first in that it allows a different 8-bit code
to be placed into each of the 24 T1 channels.
TC1 TO TC24:
TRANSMIT CHANNEL REGISTERS (Address=40 to 4F and 50 to 57 Hex)
(for brevity, only channel 1 is shown; see Table 1-3 for other register address)
(MSB)
(LSB)
C7
C6
C5
C4
C3
C2
C1
C0
TC1 (50)
SYMBOL
POSITION NAME AND DESCRIPTION
C7
C0
TC1.7
TC1.0
MSB of the Code (this bit is transmitted first)
LSB of the Code (this bit is transmitted last)
TCC1/TCC2/TCC3:
TRANSMIT CHANNEL CONTROL REGISTER (Address=16 to 18 Hex)
(MSB)
CH8
CH16
CH24
(LSB)
CH1
CH9
CH7
CH15
CH23
CH6
CH14
CH22
CH5
CH13
CH21
CH4
CH12
CH20
CH3
CH11
CH19
CH2
CH10
CH18
TCC1 (16)
TCC2 (17)
TCC3 (18)
CH17
SYMBOL
POSITION NAME AND DESCRIPTION
CH24
TCC3.7
Transmit Channel 24 Code Insertion Control Bit
0=do not insert data from the TC1 register into the transmit data
stream
1 = insert data from the TC1 register into the transmit data
stream
CH1
TCC1.0
Transmit Channel 1 Code Insertion Control Bit
0=do not insert data from the TC32 register into the transmit
data stream
1 = insert data from the TC32 register into the transmit data
stream
8.2 RECEIVE SIDE CODE GENERATION
In the receive direction there are also two methods by which channel data to the backplane can be
overwritten with data generated by the DS2152. The first method which is covered in Section 8.2.1 was a
feature contained in the original DS2151 while the second method which is covered in Section 8.2.2 is a
new feature of the DS2152.
8.2.1 Simple Code Insertion
The first method on the receive side involves using the Receive Mark Registers (RMR1/2/3) to determine
which of the 24 T1 channels should be overwritten with either a 7Fh idle code or with a digital milliwatt
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DALLAS [ DALLAS SEMICONDUCTOR ]
