Printronix S828, Programmer'S Manual

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Programmer Manual PTX ‐ S828
Chapter 5 IPDS Programming Information 175 260071 ‐ 001A
Description Value
Current Position X, Y = 0, 0
Arc Parameters P = Q = 1, R = S = 0
Foreground Mix Overpaint
Background Mix Leave Alone
Character Precision Character Precision
Marker Precision Character Precision
Marker Symbol Set Resident Set in Printer
Note:
Standard NLQ text character images (18 1/144 in. high by 20 1/200 in. wide) map to the standard
size graphics character so that their upper left corners are coincident.
Write Graphics (WG)
Length D685 Flag Correlation ID (Optional) DATA
BSI One or More Drawing Orders
The Write Graphics command transmits graphic data to the printer. The data in this command consists of
picture segments that contain the drawing orders that define the picture in the graphic medium
presentation space. Any number of Write Graphics commands may follow the Write Graphics Control
command.
The Write Graphics command has a data length restriction of 32K. Within this data-length limit, the Write
Graphics command can transmit partial segments, full segments, multiple segments, or any combination of
these. Segments and drawing orders must be transmitted in the order in which they are to take effect.
When the printer encounters a partial segment, the printer expects the next graphics data to be the
remainder of the segment. This condition is called graphics spanning. For a spanned segment, the
segment length is the length of the entire segment before spanning. The Write Graphics command length
is the actual number of bytes being transmitted in the current command.
The valid sequence for graphics spanning is as follows:
● Write Graphics command with zero or more segments, followed by the start of a partial segment
● Zero or more XOA, NOP, or STM commands
● A new Write Graphics command with a continuation of the partial segment, followed by zero or more
segments.
All segments are run in deferred mode; drawing orders are included in the picture as they are received.
The printer does not retain or store the segments. Receipt of the first segment starts the drawing process.
Begin Segment Introducer (BSI)
BSI One or More Drawing Orders
The Begin Segment Introducer precedes all of the drawing orders that are together in the graphic
segment. The following chart shows the format of the BSI: