HP 4 FAMILY - Manual (Page 53)

Logical Operation
Command
Specifies the logical operation to be performed in RGB color
space on the destination, source and texture to produce new
destination data.
?*l#O
# = Logical operation value (see Table 2-6)
Default = 252 (TSo)
Range = 0 to 255
Note When source and/or pattern transparency modes are set
opaque (not defaulted), values specified by this command
map directly to the ROP3 (raster operation) table values on
the following page. However, when source and/or pattern
transparency modes are set transparent, the additional
operations shown on the previous page must be performed
to achieve the final result.
Logical operations in the table are shown in RPN (reverse
polish notation). For example, the value 225 corresponds to
TDSoxn, the logical function of
NOT (texture XOR (source OR destination))
Notes This command is the PCL Version of the HP-GL/2 MC
command.
This command sets the ROP value which affects not only
PCL operation but also the HP-GL/2 ROP value.
Printer-Specific Differences 2-17