what is a "valid SOH"?

[Frank Moore <fmoore@xxxxxxxxxxxx>]

Everyone,

  I am working on the AIS-L detection logic of a WIS module. Clause
50.3.9.1.5 states "The AIS-L functionality implemented by the WIS is
described in 50.3.2.5 and defined fully in Section 7.4.1 of ANSI
T1.416-1999."

ANSI T1.416-1999 states "Line AIS is a STS-N(c) signal containing a
valid SOH with bits 6,7 and 8 of the K2 byte set to 111, and a scrambled
all-ones pattern for the remainder of the signal"

My question is what consistutes a "valid SOH" for a WIS frame. Do I need
to verify 192 A1s followed by 192 A2s or do I just verify that the sync
point happened correctly (ie A1/A2 at byte 192/193). Do I need to verify
that the Z0s are all 0xcc? Do I need to check that all of the unused
bytes are 0x00?

I guess AIS-L doesn't seem so fully defined to me :)

Frank


Frank Moore
Sr. Staff Engr.
Mitsubishi Electric & Electronics
DECE
Durham, NC 27713
(919) 767-7764