PEB2080 SIEMENS [Siemens Semiconductor Group], PEB2080 Datasheet - Page 50

• Manufacturer Part Number: PEB2080
• Description: S/T Bus Interface Circuit(SBC)
• Manufacturer: SIEMENS [Siemens Semiconductor Group]

NT Mode
G1 deactivated
The SBC is not transmitting. No signal is detected on the S/T interface, and no activation command
is received in C/l channel. EI is output as a response to RST, DIU is output in the normal deactivated
state, and TIM is output as a first step when an activation is requested from the S/T interface.
G1 i1 detected
An INFO1 is detected on the S/T interface, translated to an “Activation Request Upstream”
indication in the C/l channel. The SBC is waiting for an ARD command, which normally indicates
that the transmission line upstream (usually a two-wire interface) is synchronized.
G2 pend. act.
As a result of the ARD command, an INFO2 is sent on the S/T interface. INFO3 is not yet received.
G2 synchronized
INFO3 was received, INFO2 continues to be transmitted while the SBC waits for a “switch-through”
command AID from the device upstream.
G3 activated
INFO4 is sent on the S/T interface as a result of the “switch through” command AID: the B and D
channels are transparent. In case of loss of synchronism of the NT receiver, lNFO2 is sent (Version
A7 and following).
Lost framing U
On receiving a RSYD command which usually indicates that synchronization has been lost on the
two-wire interface, the SBC transmits continuous alternating pulses.
G4 pend. deact.
This state is triggered by a deactivation request DR, and is an unstable state. Indication DIU (state
“G4 unackn.”) is issued by the SBC when:
G4 unacknowledged
Final state after a deactivation request. The SBC remains in this state until an “acknowledgment” to
DIU (DID) is issued, without which a new activation is impossible.
Test mode continuous pulses
Continuous alternating pulses are sent.
Test mode single pulses
Single alternating pulses are sent (2-kHz repetition rate).
Semiconductor Group
– either INFO0 is received during 16 ms
– or an internal timer of 32 ms expires.
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Operational Description