I have a HP PSC 1315 printer, scanner, copier. The instruction manual
and the printer itself say to use 27 or 56 black, and 28 or 57 color
cartridges. I have a couple of 21 black and one 22 color cartridges
that are unopened. The pins and physical mounting appear to be
identical to the newer cartridges. I know that I can just put the
cartridges in and see what happens, but does anyone know for sure if
these older cartridges can definitely be used?