4248 FCB Module Structure

The FCB data following the header information consists of at least five bytes: a flag byte (X'7E'), a control byte (containing information about the horizontal copy feature and printer speed), an offset byte, one or more FCB data bytes (similar to the 3800 data byte for each physical line of the form), and an end-of-sheet byte (X'FE'). The syntax of the 4248 FCB module is shown in Figure 1.

Figure 1. 4248 FCB Module Structure

The control byte is a bit pattern describing whether the horizontal copy feature is active and what printer speed is to be set when the FCB is loaded into the buffer. The structure of the control byte is shown in Figure 2.

Figure 2. 4248 FCB Module Control Byte

Notes to Figure 2

¹: IEBIMAGE sets these bits to zero. For more information on the stacker drop rate and stacker level control bits, see the appropriate hardware manual for your printer.
²: If the module is used by a 3262 Model 5 printer, these bits are ignored.

The offset byte follows the control byte and is set either to zero or to the print position of the horizontal copy (2 through 168).

The data byte is a bit pattern similar to that produced for the 3800 printing subsystem. Each data byte describes one of 12 channel codes for vertical forms positioning and one of the allowed lines-per-inch codes for vertical line spacing. The structure of the data byte is shown in Figure 3.

Figure 3. 4248 FCB Module Data Byte

The total number of lines defined in the module must be equal to the length of the form.