For all your HP 7470a plotter manual needs

On the off chance you need to control a 30 year old graphics plotter, have I got something for you:

HP-7470A_Graphics_Plotter-Interfacing_and_Programming_Manual

The image links to a scanned copy of the HP 7470A Graphics Plotter: Interfacing and Programming Manual which I found on the web, and cleaned up. The pages have been OCR’d, so it should be searchable.