Thank you. 
I've discovered Tilengine. As it's creator said:
It's not a complete game development kit, it's specifically a graphics-only library. Think of it as a kind of virtual 2D graphics chip that must be paired with other components.
I asked and he said me that:
It was originally designed without any windowing system, you must provide an external surface for rendering in a compatible pixel format.
(...)
Tilengine uses an ARGB pixel format for 32 bpp, and packed 565 RGB for 16 bpp.
I have no idea about how to do that, even if it is possible use Tilengine along with Allegro. Did somebody tested it? Do you have an idea about how can be used?
]]>If I understand correctly, he means it will write, in memory, at the address you provide.
For example in Allegro 4 you pass screen->line[0] : The address of the first (top left) pixel.
For Allegro 5, you can use al_lock_bitmap and grab that information from ALLEGRO_LOCKED_REGION.
]]>Thank you.