DS2155 datasheet(46/238 Pages) DALLAS

46 / 238 page

DS2155

46 of 238

9. T1 FRAMER/FORMATTER CONTROL AND STATUS REGISTERS

The T1 framer portion of the DS2155 is configured through a set of nine control registers. Typically, the

control registers are only accessed when the system is first powered up. Once the DS2155 has been

initialized, the control registers only need to be accessed when there is a change in the system

configuration. There are two receive control registers (T1RCR1 and T1RCR2), two transmit control

registers (T1TCR1 and T1TCR2), and a common control register (T1CCR1). Each of these registers is

described in this section.

9.1 T1 Control Registers

T1RCR1

T1 Receive Control Register 1

03h

Bit #

Name

—

ARC

OOF1

OOF2

SYNCC

SYNCT

SYNCE

RESYNC

Default

Bit 0/Resynchronize (RESYNC). When toggled from low to high, a resynchronization of the receive-side framer

is initiated. Must be cleared and set again for a subsequent resync.

Bit 1/Sync Enable (SYNCE)

0 = auto resync enabled

1 = auto resync disabled

Bit 2/Sync Time (SYNCT)

0 = qualify 10 bits

1 = qualify 24 bits

Bit 3/Sync Criteria (SYNCC)

In D4 Framing Mode:

0 = search for Ft pattern, then search for Fs pattern

1 = cross couple Ft and Fs pattern

In ESF Framing Mode:

0 = search for FPS pattern only

1 = search for FPS and verify with CRC6

Bits 4, 5/Out-of-Frame Select Bits (OOF2, OOF1)

OOF2

OOF1

Out-Of-Frame Criteria

2/4 frame bits in error

2/5 frame bits in error

2/6 frame bits in error

Bit 6/Auto Resync Criteria (ARC)

0 = resync on OOF or RCL event

1 = resync on OOF only

Bit 7/Unused, must be set to 0 for proper operation

DS2155 Datasheet(PDF) 46 Page - Dallas Semiconductor

DS2155 Datasheet(HTML) 46 Page - Dallas Semiconductor

Html Pages

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 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL