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PEB 20321
PEF 20321
Host Memory Organization
Data Sheet
297
2001-02-14
–
Transmit Off
(not supported by LBI)
TI =
‘
0
’
, TO =
‘
1
’
, TA =
‘
0
’
(clears a previous transmit abort condition, sets a transmit
off condition, effects only the serial interface)
The Tx channel is disabled immediately, i.e. the Tx formatter is reset and the Tx buffer
is not accessed for this channel. The output time slots are tristated. Upon leaving the
transmit off mode the transmit link list must be initialized by a transmit reinitialize
command. Otherwise the transmission will be started with the remaining data still
stored in TB and continue with the old link list. If a loop condition is set the transmit off
does not reset the Tx formatter, it only tristates the serial output line.
After the transmit off condition is cleared by the transmit initialize command.
In HDLC, TMB, TMR, V.110/X.30 the device starts with the interframe time-fill
7E for HDLC and IFTF =
‘
0
’
FF for HDLC and IFTF =
‘
1
’
00 for TMB, TMR, V.110/X.30
and then with the frame in the descriptor at FTDA. For V.110/X.30 this descriptor
must
have the V.110-bit set and point to the E-, S-, X-bits, the data are then at the next
Tx descriptor.
In TMA mode the device starts with the interframe time-fill
TFLAG
for FA =
‘
1
’
FF
H
for FA =
‘
0
’
and then with the data in the descriptor at the FTDA.
Note: It is recommended to set bit-field
‘
Mode
’
located in the first DWORD of the
Channel Specification to
‘
00
’
(Transparent Mode A) together with any
‘
Transmit
Off
’
channel command. This ensures octet to timeslot aligned transmission after
re-initialising the channel again.
–
Transmit Abort
(not supported by LBI)
TI =
‘
0
’
‘
1
’
, TA =
‘
1
’
(clears transmit off condition, sets transmit abort condition,
affects only the serial interface)
This abort is performed in the transmit formatter at the serial interface. The currently
transmitted frame is aborted by the sequence:
011 1111 1111 1111 for HDLC
00
H
for TMB
0000
H
for TMR
3 frames with erroneous synchronization pattern for V.110/X.30
TFLAG
for TMA, FA =
‘
1
’
FF
for TMA, FA =
‘
0
’
.
–
Afterwards or, if no frame is currently sent, directly inter frame time fill:
7E
for HDLC and IFTF =
‘
0
’
FF
for HDLC and IFTF =
‘
1
’
00
for TMB, TMR, V.110/X.30
TFLAG
for TMA, FA =
‘
1
’
FF
for TMA, FA =
‘
0
’