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7KH GDWD UHJLVWHU VKRZQ LQ 7DEOH FDQ EH ZULW
WHQ WR WKH VHULDO S RUW 'DWD L V LQSXW RQ WK H H LJKW
FORFN F\F OHV L PPHGLDWHO\ I ROORZLQJ WK H DG
GUHVVFRPPDQG E\WH %LWV DQG DU H XV HG WR
FOHDU DQ LQW HUUXSW LVVXHG IURP WKH ,17 SLQ ZKLFK
RFFXUV LQ UHVSRQVH WR D ORVV RI VLJQDO RU D SUREOHP
ZLWK WKH RXWSXW GUL YHU ,I ELWV RU DUH WUX H WKH
FRUUHVSRQGLQJ LQWHUUXSW LV VXSSUHVVHG 6R LI D ORVV
RI VLJQDO LQWHUUXSW LV FOHDUHG E\ ZULWLQJ D W R ELW
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ELW 7KLV KROGV IRU '30 DV ZHOO
LSB: first bit in 0 clr LOS Clear Loss of Signal
1 clr DPM Clear Driver Performance Monitor
2 LEN0 Bit 0 - Line Length Select
3 LEN1 Bit 1 - Line Length Select
4 LEN2 Bit 2 - Line Lenght Select
5 RLOOP Remote Loopback
6 LLOOP Local Loopback
MSB: last bit in 7 TAOS Transmit All Ones Select
Table 8. Input Data Register
:ULWLQJ D WR HLWKHU &OHDU / 26 RU &OHDU
'30 RYHU WKH VHULDO LQWHUIDFH KDV WKUHH HIIHFWV
WKH F XUUHQW L QWHUUXSW RQ WK H VH ULDO LQWHUIDFH
ZLOO EH FOH DUHG 1RWH W KDW VL PSO\ U HDGLQJ WK H
UHJLVWHU ELWV ZLOO QRW FOHDU WKH LQWHUUXSW
RXWSXW GDWD ELWV D QG ZLOO EH UHVHW DV
DSSURSULDWH
IXWXUH LQWHUUXSWV IRU W KH FRUUHVSRQGLQJ /26
RU '30 ZLOO EH SUHYHQWHG IURP RFFXULQJ
LSB: first bit in 0
1
2
3
4
LOS
DPM
LEN0
LEN1
LEN2
Loss of Signal
Driver Performance Monitor
Bit 0 - Line Length Select
Bit 1 - Line Length Select
Bit 2 - Line Lenght Select
Table 9. Output Data Bits 0 - 4
Bits
567
Status
Reset has occurred or no program input.
TAOS in effect.
LLOOP in effect.
TAOS/LLOOP in effect.
RLOOP in effect
DPM changed state since last "clear DPM"
occured.
LOS changed state since last "clear LOS"
occured.
LOS and DPM have changed state since
last "clear LOS" and "clear DPM".
Table 10. Coding for Serial Output Bits 5, 6, 7
:ULWLQJ D WR HLWKHU &OHDU /26 RU & OHDU
'30 H QDEOHV W KH F RUUHVSRQGLQJ L QWHUUXSW I RU
/26 RU '30
2XWSXW GDWD IURP WKH VHULDO LQWHUIDFH LV SUHVHQWHG
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DQG PXV W EH GH FRGHG &RGHV DQG
ELWV DQ G LQ GLFDWH / 26 DQ G ' 30 V WDWH
FKDQJHV :ULWLQJ D WR WKH &OHDU /26 DQGRU
&OHDU '30 ELWV LQ WKH UHJLVWHU DOVR UHVHWV VWDWXV
ELWV DQG
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