PEB2085 SIEMENS [Siemens Semiconductor Group], PEB2085 Datasheet - Page 210

• Manufacturer Part Number: PEB2085
• Description: ISDN SubscribernAccess Controller
• Manufacturer: SIEMENS [Siemens Semiconductor Group]

SAW
WOV
4.1.10
Semiconductor Group
Subscriber Awake
Used only if terminal specific functions are enabled (STCR:TSF = 1).
Indicates that a falling edge on the EAW line has been detected, in case the terminal
specific functions are enabled (TSF-bit in STCR).
Watchdog Timer Overflow
Used only if terminal specific functions are enabled (STCR:TSF = 1).
Signals the expiration of the watchdog timer, which means that the processor has
failed to set the watchdog timer control bits WTC1 and WTC2 (ADF1 register) in the
correct manner. A reset pulse has been generated by the ISAC-S.
7
Used in auto-mode only.
XAD1 contains a programmable address byte which is appended automatically to the
frame by the ISAC-S in auto-mode. Depending on the selected address mode XAD1
is interpreted as follows:
* 2-Byte Address Field
XAD1 is the high byte (SAPI in the ISDN) of the 2-byte address field. Bit 1 is
interpreted as the command/response bit "C/R". It is automatically generated by the
ISAC-S following the rules of ISDN LAPD protocol and the CRI bit value in SAP1
register. Bit 1 has to be set to "0".
In the ISDN LAPD the address field extension bit "EA", i.e. bit 0 of XAD1 has to be
set to "0".
* 1-Byte Address Field
According to the X.25 LAPB protocol, XAD1 is the address of a command frame.
Note: In standard ISDN applications only 2-byte address fields are used.
Transmit Address 1
C/R Bit
Command
0
1
Response
1
0
210
XAD1
Transmitting End
subscriber
network
Write
Register Description
CRI Bit
0
1
Address 24
0
H