Compuprint 4247-Z03 Programmer Manual - Manual (Page 145)

Activate Printer Alarm (APA)
The XOA Activate Printer Alarm (APA) subcommand signals the printer to activate the alarm mechanism.
As long as the printers alarm function is enabled, the alarm will be turned on in response to this command.
It will remain on until Stop is pressed.
After processing this command, the printer continues to process the incoming IPDS data stream. If
synchronization of actions is desired, the application must ensure if the appropriate commands are sent to
the printer.
Discard Buffered Data (DBD)
The XOA Discard Buffered Data (DBD) subcommand deletes all buffered data from the printer storage and
returns the printer to home state. Any data currently being received is deleted. If this order is syntactically
correct, no exceptions can result from its execution. The DBD order does not affect completely received
resources, such as fonts, page segments, and overlays; however, if the printer is in any resource state, the
printer deletes the partial resource before returning to home state. If the printer is in Ordered Page Mode,
the subcommand prints all buffered data to the point of the command, does a page eject, and returns to
Home State.
The DBD order is a synchronizing command. Any command following a synchronizing command is not
processed until all preceding commands have been completely processed. Also, the ACK of the DBD order
is not returned until DBD processing is complete.
Request Resource List (RRL)
This subcommand is a request from the host application program for the printer to identify resources
currently allocated in the printer. The printer responds by placing the requested information in the Special
Data (SD) area of a subsequent Acknowledge Reply.
The subcommand and subcommand data field has the following format:
Decimal Hex Value Description
0-1 0-1 F400 RRL Order Code
2 2 FF Device Defined Ordering
3-4 3-4 XXXX Entry Continuation Indicator (See Note 1)
5 5 03 - FF Entry Length
6 6 Resource Type Requested (See Note 2)
01 Single Byte Fonts
04 Page Segments
05 Overlays
FF All Resources
7 7 00 Resource ID Format
Host-Assigned Resource ID
8-9 8-9 XXXX Resource ID (See Note 2)
Notes:
1. If the entire resource list does not fit in the Special Data Area of the Acknowledge Reply, continuation is
necessary which the 4247 Printer will indicate using the Acknowledgement Continuation bit in the flag byte of the
Acknowledge Reply. If the host requests Acknowledgement Continuation by sending a command with ARQ bit
and the Continuation bit set, the printer will complete the RRL reply using Acknowledgement Continuation. If the
host requests RRL continuation (by sending an RRL command with nonzero values in bytes 3 and 4), the printer
will use continuation, the printer will default to RRL continuation.
2. For overlays, segments, and symbol sets, this is their two byte ID. This field is omitted when the resource type
equals All.
Chapter 4. IPDS Programming Information 125