Int 7F  - Telebit Acs Serial I/o                                           [S]

   ES:SI-> parameter block

Return: CF set on error
   CF clear on success

Notes: the signature "PDGATEWRKSTNIF" appears just prior to the interrupt
     handler; this serves as the installation check
Index: installation check;Telebit ACS Serial I/O

Format of Telebit ACS parameter block:
Offset Size    Description
 00h   BYTE    command (see below)
 01h   BYTE    gateway number
 02h   BYTE    reserved
 03h   BYTE    port
 04h 17 BYTEs  auxiliary buffer
 15h   BYTE    session
 16h   WORD    count of bytes passed to API
 18h   DWORD   buffer pointer passed to/from API
 1Ch   WORD    count of bytes passed from API
 1Eh   BYTE    return code (see below)

Values for command:
 3Ch   status
 3Dh   connect
 3Eh   disconnect
 3Fh   read
 40h   data/command write
 41h   clear receive buffer
 42h   get configuration
 43h   get receiver status
 44h   raw write
 45h   search servers
 46h   set transmit buffer size

Values for return code:
 00h   success
 01h   invalid session
 05h   servername invalid
 06h   NetWare fileserver bindery is locked
 07h   communication server not active
 08h   general failure in NetWare fileserver
 09h   not logged into a fileserver
 10h   connection table full
 11h   no response from communication server
 12h   connection attempt terminated abnormally
 13h   connection refused - no sessions available
 14h   gateway number/port already in use
 15h   invalid connection response
 16h   port invalid
 17h   incorrect version in server response
 18h   gateway number/port combination not configured
 19h   initialization has not been completed
 20h   no more sockets are available
 21h   no active poolname
 23h   FATAL internal interface error
 24h   registration of host workstation failed - name is already in use
 25h   registration of host workstation failed - workstation name table full
 26h   registration of host workstation failed - only one session may be
     registered for dial-in
 FFh   Telebit ACS API is busy - retry later