I found this:
http://www.biopdf.com/guide/print_pdf_from_command_line.php
PDFCMD command="printpdf"
Additional parameters for printing PDF documents
input File name of PDF document to print.
pdfprinter (optional) Name of PDF printer used for the operation.
printer (optional) Name of the printer that should receive the print job.
firstpage (optional) First page to print. Default is the first page.
lastpage (optional) Last page to print. Default is the last page.
scaletofit (optional) Scale output to fit (yes|no). Default is yes.
bpp (optional) Bits per pixel. Valid values are 1, 4, 8, 24 (default).
docname (optional) Document name in printer queue.
maxdpi (optional) Maximum DPI resolution to print.
timeout (optional) Maximum timeout in seconds for the merge
to finish. The default is 60 seconds.
Example:
PDFCMD command=printpdf input="C:\Temp\A.pdf"