2 control bus, Control bus -3, Control buses -3 – EFJohnson 3000 SERIES User Manual
Page 23: Architecture 3-3, Netnim, Dcms, Tims, Snms, Wams, Lems

ARCHITECTURE
3-3
3.3.2 CONTROL BUS
The following are descriptions of control buses.
Refer to Figure 3-3.
1. The IDB Idle/Collision line is a three level line that
indicates if the line is idle, busy or collision
occurred for the IDB communication process. This
provides for high speed CSMA of the IDB.
Figure 3-3 CONTROL BUSES
CIMs
CCMs
NETWORK
INTERFACE
MODULE
NetNIM
CONVENTIONAL
CHANNEL
MODULE
INTERFACE
CHANNEL
MODULE
INTRA-TERMINAL DATA BUS (IDB) IDLE / COLLISION
CHANNEL STATUS BUS (CSB) IDLE / COLLISION
DISPATCH
MODULE
CHANNEL
DCMs
TELEPHONE
MODULE
INTERFACE
TIMs
NETWORK
SYSTEM
MODULE
SNMs
WIDE
MODULE
AREA
WAMs
LOGGING
MODULE
ENCODER
LEMs
DISPATCH
MODULE
INTERFACE
DIMs
2. The CSB Idle/Collision line is a three level line that
indicates if the line is idle, busy or collision
occurred for the CSB communication process. This
provides high speed CSMA of the CSB.