Use this command to show the settings of the various PRF parameters. Use the READ command to display the names of currently queued files. If the filename is omitted, the last file to be queued by this process is cancelled. This command is only effective for files which have not yet physically begun to print. Issue the DM command ICON to change the icon window into its full-size format.
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Otherwise, repack and print the non-zero portion of the printer buffer. Note that the two high order bits in each byte must be set to 1 even though they are not printed. If so, then we don't need to repack the bits in this section, we just set the output buffer to the correct constants. The printer will actually shut itself off if the duty cycle is too high. The checkerboard pattern used to print the buffer helps to lessen the steaking that occurs when a totally black buffer is printed.