Connect USB-Printers to custom specific hardware

Hi all,

in the past we have connected printers with Centronics (LPT)-interface to our microcontroller-based hardware for printing xy or xt-diagrams written by small and effective software routines. This could be done because bitmap-printing was a simple open "standard".

Now parallel-interface-printers are extended to the EPP or ECP-Mode, they get more and more rare (and sometimes expensive like fossiles) and are substituted consequently by USB- devices.

We were not yet successful in finding a comparable USB-based solution. It starts with the problem that every printer manufacturer seems to make his own driver for every printer model and that all these are either Windows- or MAC-based and not "open". It seems to be not possible to get the producers driver specs.

Does someone know a standard solution (or a way towards that ...) for using a USB-printer (lets say HP, Canon or something widely spread over the world like that - its necessary because the hardware is sold nearly everywhere) ?

Thanks for thoughts Uwe