Data Chaining Query Reply; 3270 Ipds Query Reply; Programming Dependencies; Bsc - IBM 6400 Programmer's Reference Manual

IPDS for Control Units

Data Chaining Query Reply

This query reply indicates that data-chaining is valid in the non-SNA
environment. This is an inbound field only. The format of this field is:

3270 IPDS Query Reply

This query reply indicates that IPDS is valid in the non-SNA environment. This is
an inbound field only. The format of this field is:

Programming Dependencies

The use of IPDS requires the following programming support outside of the 3174
and 3274 Control Unit.

BSC

The Write Structured Field (WSF) command sends IPDS data from the application
program to the printer. This data (contained within structured fields) does not
include a WCC. In IPDS mode, the start of printing depends on the content of the
data stream and conditions within the printer.
Transmissions to a printer in IPDS mode can therefore receive either an ACK
reply or a WACK reply from the control unit. The WACK reply is the only
positive indication that BSC sense/status indicating device end subsequently is
sent by the control unit.
192
6400 IPDS
Byte Value Description
0-1 0006 Structured Field Length
2 81 Query Reply
3 98 Data Chaining
4 80 Direction (to Device Only)
5 00 Reserved
Byte Value Description
0-1 0008 Structured Field Length
2 81 Query Reply
3 9A 3270 IPDS
4-5 0000 Reserved
6-7 0FB0 Maximum Allowable Outbound Transmission Size