Appendix: The CAPI Drivers
MicroLink ISDN/PCC-16
Manual © 1997 ELSA GmbH
25
C
The CAPI Drivers
The CAPI interface (
C
ommon ISDN
A
pplication
P
rogramming
I
nterface
) is a standardized software
interface between ISDN adapters and ISDN application software. As this interface is completely
handled by the application software, its details need not be explained (unlike the AT command
interface described elsewhere in this manual).
◊
NOTE
◊
A detailed documentation of the CAPI-Interface can be downloaded from the
ELSA ONLINE
Support BBS (see page 42 for ISDN/modem numbers) or from
the ELSA forum in CompuServe. The following section only describes some
specific details of this implementation.
The CAPI 1.1 Driver
Implementation
The supplied CAPI 1.1 drivers support CAPI version 1.1, profile A, release date
details
September 07, 1990, with the following limits:
n
Two input buffers for request and responses with 384 bytes each.
n
Both B channels can be used simultaneously and independent of one-
another for ISDN communications, not only within a single application
but also by different applications.
n
One B3 connection (NCCI) can be established per B channel (PLCI).
n
Up to 64 B3 data buffers (per data direction) can be requested.
n
Up to 8 applications can be registered simultaneously.
n
Up to 64 received messages per application.
n
Up to 24 Tx/24 Rx buffers per B3 connection.
1)
n
Up to 2051 bytes per B3 data buffer.
1)
If more B3 data buffers are specified in the installation, this maximum value is
used instead.
CAPI error codes
The following additional error codes have been implemented:
31FFh
No more connection possible for this application
32FEh
No more B3 connection available
32FFh
No more B channel available
