The Hayes Modem technical reference is available at Archive.org. https://archive.org/details/Hayes44012TechnicalReferenceForHayesModemUsers1993 https://archive

The Hayes Modem technical reference is available at Archive.org. https://archive.org/details/Hayes44012TechnicalReferenceForHayesModemUsers1993 https://archive.org/details/Hayes44012TechnicalReferenceForH... But I have an original spiral-bound paper copy - if you want it, email me and I'll send it to you. Include the Fidonet ascii-art dog in your email.