Take note also that to provide the software stack to operate a FAX modem from an 8051 type processor will most likely draw the rope tight around the 8051's neck. The protocol is not simple and there is a whole back and forth process that goes on that allow for FAX transmission to occur.

If the original poster is interested in "printing" at a remote location without having a whole PC type computer present at the far end a print logging system can be rigged up with an off the shelf standalone serial printer and a standalone modem. (This kind of of thing was very common back in the days of a time gone by (say the '70s and '80s). As a matter of fact it was rather common that a modem was connected to a 24x80 terminal (often called a glass teletype) and an ASCII style printer was connected to a second RS232 port on the back of the terminal. The host could then send data to the screen or to the printer and switching between the two via ESC-sequences sent through the modem to the terminal.

Beware that these days if you try to set up a remote "print logging system" that you will have to choose your printer with care. Not any modern cheap PC printer is going to work as they are often parallel and/or limited to being a dumb graphics mechanism controlled by Windows or MAC software drivers. Look specifically for Serial ASCII type printers. There are plenty of old used laser printers around that can work in this manner. There were also at one time a huge selection of combo serial/parallel dot matrix printers which would work too. Sometimes you can find these for next to nothing at garage sales or electronics surplus outlets. But at the same time these printers use tractor feed paper.

Michael Karas