PSB7115 Datasheet, PDF (133/264 Pages) Siemens Semiconductor Group – Enhanced ISDN Data Access Controller ISAR 34

PSB 7115
Operational Description
DPS …
Datapath selection
01:
path 1
10:
path 2
VCMD …
V.110 Command (VCMDH, VCMDL)
Contains one of the V.110 commands listed below. A third parameter
must be written to the mailbox which is different for each of the
commands.
01F0h:
01F1h:
01F2h:
01F3h:
01F4h:
01F5h:
Clamp Control
According to the parameter CCT either user data (CCT=00),
0-bits (CCT=01) or 1-bits (CCT=11) are transmitted.
Set S-,X-bits (for transmitter)
The S- and X-bit setting is defined in the 3. parameter.
Set E-bits (for transmitter)
The E-bit setting is defined in the 3. parameter.
Delay of synchronisation (for receiver)
By default, frame synchronisation is achieved with the first
V.110 frame that is received correctly.
This command tells the pump control the number of V.110
frames which must be received correctly before
synchronisation is achieved. The 3. parameter defines this
number in the range 01h - FFh.
Enable mailbox buffer empty indication (for transmitter)
If enabled, the ISAR 34 will release a status event to the host
as soon as the last data in the mailbox buffer is transmitted
and the host can set control bits after the last valid data has
been transmitted. The status event will only be released once
for a buffer empty condition, for a further state transition from
“not empty” to “empty”, the indication has to be reenabled
again. The 3. parameter must be set to ’1’.
Enable / Disable DTE control messages
A status change of the remote DTE is can be indicated to
the host by status events (NOM = 0). The host can select the
type of status events to be received by enabling (’1’) or
disabling the corresponding flag in the 3. parameter.
For the V.110 commands “Set clamp to 0/1” (VCMD = 11h/13h) data
must not be entered to the mailbox for transmission. If a clamp is set and
continuous 0-bits or 1-bits are transmitted, mailbox data will be
discarded by the ISAR 34.
Semiconductor Group
133
02.98