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Data Sheet
January 1998
T7256 Single-Chip NT1 (SCNT1) Transceiver
4
Lucent Technologies Inc.
Table of Contents
(continued)
Tables
Page
Table 1. Pin Descriptions...........................................................................................................................................6
Table 2. U-Interface Bit Assignment ........................................................................................................................13
Table 3. Line Transmission Code.............................................................................................................................18
Table 4. Global Device Control—Device Configuration (Address 00h)....................................................................20
Table 5. Global Device Control—U-Interface (Address 01h) ...................................................................................22
Table 6. Global Device Control—S/T-Interface (Address 02h).................................................................................23
Table 7. Data Flow Control—U and S/T B Channels (Address 03h)........................................................................25
Table 8. Data Flow Control—D Channels and TDM Bus (Address 04h)..................................................................26
Table 9. TDM Bus Timing Control (Address 05h).....................................................................................................27
Table 10. Control Flow State Machine Control—Maintenance/Reserved Bits (Address 06h) .................................28
Table 11. Control Flow State Machine Status (Address 07h) ..................................................................................29
Table 12. Control Flow State Machine Status—Reserved Bits (Address 08h) ........................................................30
Table 13. eoc State Machine Control—Address (Address 09h) ..............................................................................31
Table 14. eoc State Machine Control—Information (Address 0Ah) .........................................................................32
Table 15. eoc State Machine Status—Address (Address 0Bh) ...............................................................................32
Table 16. eoc State Machine Status—Information (Address 0Ch) ..........................................................................32
Table 17. Q-Channel Bits (Address 0Dh).................................................................................................................33
Table 18. S Subchannels 1—5 (Address 0Eh—12h)...............................................................................................33
Table 19. U-Interface Interrupt Register (Address 13h)...........................................................................................34
Table 20. U-Interface Interrupt Mask Register (Address 14h)..................................................................................35
Table 21. S/T-Interface Interrupt Register (Address 15h).........................................................................................36
Table 22. S/T-Interface Interrupt Mask Register (Address 16h)...............................................................................36
Table 23. Maintenance Interrupt Register (Address 17h)........................................................................................37
Table 24. Maintenance Interrupt Mask Register (Address 18h)...............................................................................37
Table 25. Global Interrupt Register (Address 19h) ..................................................................................................38
Table 26. Stand-Alone Mode ...................................................................................................................................45
Table 27. Microprocessor Mode...............................................................................................................................45
Table 28. STLED States ..........................................................................................................................................46
Table 29. T7256 Reference Schematic Parts List....................................................................................................56
Table 30. Line-Side Resistor Requirements ............................................................................................................58
Table 31.
Motorola
MC68302 SCC Options.............................................................................................................62
Table 32. PCM Channel Selection...........................................................................................................................63
Table 33. SPEC_V2 Functions ................................................................................................................................69
Table 34. SPEC_V2 Interface Connector Pinouts....................................................................................................71
Table 35. Power Consumption.................................................................................................................................74
Table 36. Digital dc Characteristics (Over Operating Ranges) ................................................................................74
Table 37. S/T-Interface Receiver Common-Mode Rejection....................................................................................75
Table 38. Fundamental Mode Crystal Characteristics.............................................................................................75
Table 39. Internal PLL Characteristics.....................................................................................................................75
Table 40. TDM Bus Timing.......................................................................................................................................76
Table 41. Clock Timing.............................................................................................................................................77
Table 42. RESET Timing..........................................................................................................................................77
Table 43. Power Dissipation Variation....................................................................................................................101
Table 44. Power Dissipation of CKOUT .................................................................................................................101
Table 45. Power Consumption...............................................................................................................................102