DS26401 datasheet(128/309 Pages) DALLAS

128 / 309 page

DS26401 Octal T1/E1/J1 Framer

128

9.12.3 Mapping T1 Channels from a 2.048MHz Backplane

Setting the TSCLKM bit in TIOCR.4 will enable the transmit elastic store to operate with a 2.048MHz backplane (32

time slots/frame). In this mode, the user can chose which of the backplane channels on TSER will be mapped into

the T1 data stream by programming the Transmit Blank Channel Select registers (TBCS1–4). A logic 1 in the

associated bit location will force the transmit elastic store to ignore backplane data for that channel. Typically, the

user will want to program eight channels to be ignored. The default (power-up) configuration will ignore channels 25

to 32, so that the first 24 backplane channels are mapped into the T1 transmit data stream.

For example, if the user desired to transmit data from the 2.048MHz backplane channels 2–16 and 18–26, the

TBCS registers should be programmed as follows:

TBCS1 = 01h // ignore backplane channel 1 //

TBCS2 = 00h

TBCS3 = 01h // ignore backplane channel 17 //

TBCS4 = FCh // ignore backplane channels 27-32 //

TBCS1, TBCS2, TBCS3, TBCS4

Transmit Blank Channel Select Registers

1C0h, 1C1h, 1C2h, 1C3h [+ (200h x n) : where n = 0 to 7, for Ports 1 to 8]

(MSB)

(LSB)

CH8

CH7

CH6

CH5

CH4

CH3

CH2

CH1

TBCS1

CH16

CH15

CH14

CH13

CH12

CH11

CH10

CH9

TBCS2

CH24

CH23

CH22

CH21

CH20

CH19

CH18

CH17

TBCS3

CH32

CH31

CH30

CH29

CH28

CH27

CH26

CH25

TBCS4

Bits 0 to 7 / Transmit Blank Channel Select for Channels 1 to 32 (TBCS1 to 32)

0 = transmit TSER data from this channel

1 = ignore TSER data from this channel

Note that when two or more sequential channels are chosen to be ignored, the receive slip zone select bit should be

set to zero. If the ignore channels are distributed (such as 1, 5, 9, 13, 17, 21, 25, 29) then the RSZS bit can be set

to one, which may provide a lower occurrence of slips in certain applications.

DS26401 Datasheet(PDF) 128 Page - Dallas Semiconductor

DS26401 Datasheet(HTML) 128 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