Datasheet
DS26518 8-Port T1/E1/J1 Transceiver
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5. ACRONYMS AND GLOSSARY
This data sheet assumes a particular nomenclature of the T1 and E1 operating environment. In each 125μs T1
frame, there are 24 8-bit channels plus a framing bit. It is assumed that the framing bit is sent first followed by
channel 1. For T1 and E1 each channel is made up of 8 bits, which are numbered 1 to 8. Bit 1, the MSB, is
transmitted first. Bit 8, the LSB, is transmitted last.
Locked refers to two clock signals that are phase- or frequency-locked or derived from a common clock (i.e., a
1.544MHz clock can be locked to a 2.048MHz clock if they share the same 8kHz component).
Table 5-1. Time Slot Numbering Schemes
TS
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
Channel
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32
Phone
Channel
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30










