Pebble Bay On The Pulse Of Device Driver Development

Pebble Bay’s device driver development expertise enables LiDCO to update hemodynamic monitoring systems with modern USB card reader capability.

Embedded systems development consultants Pebble Bay has announced that it has been working with medical device manufacturer LiDCO Ltd, a leading supplier of minimally invasive haemodynamic monitoring equipment. Pebble Bay has provided software development services, enabling an updated version of the LiDCOrapid product to use a wider choice of card readers.

LiDCO makes a range of products that use a novel, non-invasive technique to measure the flow of blood from the heart. The LiDCOrapid product is based on PC-compatible hardware running the QNX Neutrino real-time operating system. The previous version of the LiDCOrapid monitor was controlled by a smart card via a serial link. In the new version, LiDCO have moved to a new USB-interfaced card reader, taking the opportunity to adopt a standard protocol and software component to provide the interface to the card readers, therefore abstracting the system and application software from specific details of the card reader interface.

LiDCO chose to adopt the Personal Computer/Smart Card specification (, and needed to port the existing PC/SC-Lite Linux implementation to the QNX Neutrino operating system to support their application.  Although they have the required expertise in house, LiDCO chose Pebble Bay for this project so that their staff could focus on development of the application software.

“We initially carried out a short consultancy project to investigate the technical aspects of porting the existing PC/SC-Lite software stack, including support for USB-connected smart cards, to the QNX Neutrino 6.x real-time operating system,” said Ian Willat, Managing Director of Pebble Bay. “During this consultancy, we determined what we believe to be the best approach to carrying out the port, bearing in mind LiDCO’s requirements, the technical differences between Linux and QNX Neutrino, the likely amount of effort involved in carrying out the port, and any risks we have identified.  We then documented the results of this consultancy in a technical report.”

Pebble Bay then carried out the port of PC/SC-Lite and the other required software components to QNX Neutrino for LiDCO. The project included testing the ported software at its site, followed by delivery and acceptance at LiDCO’s office in London.

“We found Pebble Bay to be very easy to work with, and their project management kept things running smoothly throughout the engagement.  Pebble Bay’s expertise in working with USB, device drivers and real-time operating systems meant that we were in safe hands, which was demonstrated by the ease with which our application software integrated with the ported PC/SC-Lite they delivered.”

As a result of Pebble Bay’s device driver development work, LiDCO’s system can now support a wider choice of card readers, with little or no change to the application software. In addition to this, with LiDCO and Pebble Bay working in parallel, it meant that development time was minimized and alongside Pebble Bay’s previous experience in working with USB device drivers, allowed them to identify and mitigate the risks associated with the port early in the project.

“I am very pleased to report that this project ran very smoothly,” stated Ian Willats. “There were some technical challenges associated with the way the USB bus was enumerated and the devices configured. However, our in-depth expertise of USB protocols and device drivers allowed us to solve these quickly and without slowing down the project.”

Pebble Bay will be exhibiting at Embedded Live, 19th – 21st October, to be held at Earls Court in London.