XRT72L13 Datasheet, PDF (322/370 Pages) Exar Corporation – M13 MULTIPLEXER/CLEAR CHANNEL DS3 FRAMER IC

XRT72L13
M13 MULTIPLEXER/CLEAR CHANNEL DS3 FRAMER IC
REV. P1.0.6
áç
PRELIMINARY
FIGURE 105. FLOW CHART DEPICTING THE FUNCTIONALITY OF THE LAPD RECEIVER
SSTTAARRTT
ENABLE THE LAPD RECEIVER
This is done by writing the value “0xFC into the
RxLAPD Control Register (Address = 0x14)
LAPD Receiver begins reading in the DL bits
from each inbound DS3 frame
DDoeoses
ththeeLLAAPPDD
RReceecievivererddeteetcetct66
NO
cocnosnesceuctuitvieve
ZZereorsos
??
11
YES
AABBOORRTTSSeqequuenencece
DDoeoses
thteheLLAAPPDD
RReceecievievrerdedteetcetct77
cocnosnesceuctuitvieve
ZZereoros _s
YES
??
NO
FFlalgagSSeqeuqeunecnece
LLAAPPDDRReceecievievrerisisreraedaidnigngininaaLLAAPPDD
MMesessasgaegeFFrarmame,e,cocnotnatianiinnigngaaPPMMDDLL
MMesessasgaeg.e.
DDoeoses
NO
ththeeLLAAPPDD
RReceecievivererddeteetcetct66
cocnosnesceuctuitvieve
ZZereorsos
??
YES
EEndndofofMMesessasgaege(E(EOOMM) ₎
VVEERRIFIFYYTTHHEEFFCCSSVVAALLUUEE
RRepeoportrtrerseusultlstsininthteheRRxLxLAAPPDD
SStattautus _{sRRegegisitsetre.r...}
“U“Unn-s-tsutuffffcocnontetnentstsofofRReceecieviveded
MMesessasgage”e”
GGeneenreartaete“R“ReceecievievdedLLAAPPDD
InItnetrerrurputp”t”
DDoeoses
ththeeLLAAPPDD
YES
RReceecievivererddeteetcetct77
cocnosnesceuctuitvieve
ZZereorsos
??
NO
WWrirtieteRReceecievivededPPMMDDLLMMesessasgagee
initnotothteheRReceecievieveLLAAPPDDMMesessasgaege
BBufuffefrer(A(Adddrdersessesses0x0DxDEE- _{-0x01x3153)5)}
EExxeceucuteteRReceecieviveeLLAAPPDD
InIntetrerruruptptSSerevrvicieceRRooutuitninee
11
NOTES:
1. The “white” (e.g., unshaded) boxes reflect tasks
that the user’s system must perform in order to con-
figure the “LAPD Receiver” to receive LAPD Mes-
sages.
2. A brief description of the steps that must exist
within the “Receive LAPD Interrupt Service” routine
exists in Section 3.3.6.
4.3.4 The Receive Overhead Data Output Inter-
face
Figure 106 presents a simple illustration of the "Re-
ceive Overhead Data Output Interface" block within
the XRT72L13.
310