Compuprint 4247-Z03 Programmer Manual - Manual (Page 116)

WGC (Write Graphics Control): The WGC command causes the printer to enter the graphics block state.
Parameters in this command specify the placement, size, and orientation of the graphics block.
WG (Write Graphics): The WG command sends graphics data to the printer. The graphics data
(contained in drawing orders) specifies the various elements of the graphic. These include color, size, line
type, line width, and other parameters. One or more WG commands present the graphics picture.
END (End): The END command terminates the graphics block state. The printer remains in the overlay
state with the graphics block as part of the overlay.
WT (Write Text): This command is repeated at this point in the sequence to illustrate that additional text
data can be added to the overlay. In addition to zero or more of the WT commands, image data, bar code
data, or additional graphics data could also be included in the overlay.
IO (Include Overlay): The IO command causes a previously stored overlay to merge onto the current
overlay.
IPS (Include Page Segment): The IPS command causes a previously stored page segment to merge
onto the current overlay. An ID in this command specifies the selected page segment.
EP (End Page): The EP command causes the printer to leave the overlay state and return to the home
state. We recommend that this command contain an acknowledgment request to verify successful
transmission of the overlay.
ACK (Acknowledgment Reply): If the previous command had the ARQ bit on, the printer responds with
the ACK reply, to inform the host of successful execution of all the previous commands. This reply
indicates to the host that the printer has accepted all the overlay data and stored this information for later
printing.
Page Sequence
The page sequence causes data to print on the current page. This data can include previously stored
overlays or page segments, as well as text data. The following commands illustrate a typical page
sequence:
v
BP (Begin Page)
v WT (Write Text)
v IO (Include Overlay)
v IPS (Include Page Segment)
v WIC (Write Image Control)
v WI (Write Image)
v END (End)
v WT (Write Text)
v IO (Include Overlay)
v IPS (Include Page Segment)
v EP (End Page)
v ACK (Acknowledgment Reply).
Note: This sequence is only an example. A page can contain any combination of text, image blocks,
graphics blocks, bar code blocks, page segments, or overlays.
BP (Begin Page): The host sends the BP command to the printer, causing the printer to leave the home
state and enter the page state.
WT (Write Text): The WT command sends text data to the printer. Because the printer is currently in a
page state, this text information prints at this time. The host can send multiple WT commands to the
printer while in the page state.
96 Programmer Manual