HP PCL/PJL reference - PCL 5 Comparison Guide

2-28 Printer-Specific Differences ENWW
Merge Control Command (HP-GL/2)
The Merge Control (MC) command specifies the raster operation
(ROP's) to be performed in HP-GL/2. Raster Operations specify how
source, destination, and patterns are combined to produce final
images. This command supports all 256 Microsoft Windows ternary
(ROP3) raster-operation codes.
MC [mode, [opcode] ] ;
Merge Control Command (HP-GL/2)
1
For opcode ROP values refer to Table 2-6, Logical Operation.
mode
Note This command is the HP-GL/2 version of the PCL Logical Operation
command.
This command sets a ROP value which affects not only HP-GL/2
operation but also the PCL ROP value.
The MC command is defaulted by an IN command.
Parameter Format Functional Range Default
mode clamped integer 0 or 1 0 (ROP 252)
opcode clamped integer 0...255
1
168, 252
0 = opcode value is ignored; printer sets ROP to 252.
1 = opcode value is used as the ROP value. If no opcode value is
sent, printer sets ROP to 168. If opcode is out of range (some
value other then 0-255), the command is ignored and the
default ROP of 252 is used. (For example: MC1,60; MC1,60-;
MC1,+60; MC1,60+; all set the ROP to 60; however, MC1,-60;
or MC1,300; set the ROP to the default value (252).