UPURS - Fast serial transfer utilities for the BBC Micro

by Martin Barr

The UPURS suite provides a set of tools for the transfer of data to and from the BBC Micro series of computers using a high speed serial link.

The high speed serial link is implemented using a custom cable designed to connect to the BBC Micro computers’ User Port, presenting a standard 9-pin serial plug to the external system.

Transfer speeds of 115k baud can be achieved to and from the BBC Micro using the user port cable, reliably operating at speeds far in excess of the on board RS-423 serial port.

The accompanying software is designed to import and export single sided disc (ssd) and double sided disc (dsd) images that are used to archive software for the BBC Micro computer systems. Advanced features of UPURS allow data to be loaded directly into the memory of the BBC Micro and for ROM banks to be exported out to a connected computer.

Version 5 of the UPURS suite sees the introduction of UPCFS, a complimentary tool that allows for the "direct play" of UEF images of original cassette based software on the BBC Micro.


by sweh

UPURSFS is a new addition to the UPURS suite of applications and provides a way to use the UPURS cable with a connected PC as a remote file system. UPURSFS is based upon J.G. Harston's HostFS software which implements the Serial Tube protocol to deliver access to the PC's Hard Disc Drive. For Windows, you can use the original TubeHost application from mdfs.net and for Linux, sweh has written an implementation of TubeHost in Perl

UPURSFS installed and ready to go

The latest version of UPURSFS with source code is available on sweh's site.

Video Demonstration

In the video below, the author, Martin Barr demonstrates the use of UPURS version 3 to transfer disc images to and from a BBC Micro.

The next video shows the UPXSSD exporting an image of a corrupt disc to a PC. Errors are reported as they are found through the export process.

This final video shows how both the BBC Micro and receiving computer interact with each other to transfer the disc image to the PC for storage, backup or use with an emulator.

Contact Martin

You can contact Martin Barr directly using the UPURS contact page.

Project information

Martin's project turned into something of a group effort whilst UPURS was being developed with several people contributing their time, effort and resources to test, suggest and document UPURS and Martin would especially like to thank 'A' MartinPaulvSamwiseBigEdHugh, Pugh, Barney McGrew, Cuthbert, Dibble and Grub from the Stairway to Hell forums for their contributions to the project.

Translate this site


If you want UPURS and can't make the cable or create an EPROM or you want an Electron User Port expansion board but don't have the skills to build it, Martin has enlisted a handful of volunteers that can help you with that.

Just contact Martin and he can put you in touch with someone that can build what you need.

Get Involved!

Sign up on the Stairway To Hell forums and follow this thread to get involved in beta testing the latest updates to UPURS!

UPURS Downloads

Version 5.1 of the UPURS suite is an update to the 5.0 suite that contains several bug fixes including fixes to writing the final track of certain SSD files and also several fixes to the UPLOAD command.

To find out more about UPCFS, take a look at the UPCFS page.


UPURSFS is a new ROM image written by sweh that uses a UPURS cable to provide a HostFS filesystem over a fast serial link.

The ROM is designed to interface with TubeHost which can be downloaded from mdfs.net. The latest version of the UPURSFS ROM and a version of TubeHost for Linux can be downloaded from sweh's site here.

Previous versions

Version 4.1 supports the use of both legacy serial ports and USB to RS-232 serial cables to transfer data to and from the BBC Micro.

UPURS Watford Electronics DDFS support

UPURS Resources

Client Software

  • Hercules - for Windows
  • CuteCom - for Linux and Mac
  • UPTX - A DOS batch file to transfer ssd's to the BBC Micro without needing terminal software

UPTX was written by Dave Ault. The UPTX batch file will need minor edits to conform to your environment by specifying the correct COM port. Type UPTX /? for more information.

FTDI USB Drivers

NOTE: Drivers  prior to version 2.08.15 ar incompatible with UPURS and UPCFS. The latest WHQL approved drivers are 2.08.24 and should work fine.