Envoy ACP/XF Application Programming Manual
Normal Response Mode (NRM) Protocols
EnvoyACP/XF Application Programming Manual–132179
3-11
ASCII/EBCDIC Line Code
For a multipoint supervisor station, the tributary to which frames are being sent is
independent of the tributary from which frames are being received. That is, as long as
the supervisor station has WRITE requests pending, the supervisor can transmit data to
any tributary, regardless of whether the supervisor is receiving frames from a specific
tributary.
Only one station can own the P/F bit at any one time. Should a timeout error occur, the
supervisor station resumes ownership.
To take advantage of TWS operation, you must have full-duplex line facilities and
configure the line as full-duplex with the REJ command enabled either by using SCF or
through the application by using a SETMODE procedure call.
The requisite modifiers for TWS operation are:
•
REJ
•
FULL
If these modifiers are not enabled, EnvoyACP/XF defaults to two-way alternate
operation.
ASCII/EBCDIC Line Code
The subsystem can perform ASCII/EBCDIC translation for both incoming and outgoing
information fields.
The modifiers for EBCDIC translation are:
By calling SETMODE 19, you can alter the TRNSOFFSET and TRNSLENGTH
parameters for the duration of a particular line opening. You also can dynamically
enable and disable the translation feature by calling SETMODE 19. However, you can
call SETMODE 19 only when no other application requests are pending for the
particular line.
TRANSLATE Enables EBCDIC translation of information field.
The specified octet string within all frames that contain an
information field is automatically translated from ASCII to
EBCDIC (for WRITE operations) or from EBCDIC to ASCII (for
READ operations).
TRNSOFFSET Specifies the octet location within the information field at which
translation is to begin:
0 first octet of the information field.
1 second octet of the information field, and so forth.
TRNSLENGTH Specifies how many octets are to be translated.
Note. The address and control fields are never translated.