International Journal of Computer Applications |
Foundation of Computer Science (FCS), NY, USA |
Volume 81 - Number 12 |
Year of Publication: 2013 |
Authors: Amit Bhaira, Gaurav Rudra, Tanmoy Bag, Yusuf Husainy |
10.5120/14065-2292 |
Amit Bhaira, Gaurav Rudra, Tanmoy Bag, Yusuf Husainy . Development and Implementation of a Linux- Xenomai based Hard Real-Time Device Driver for PCI Data Acquisition System (DAS) Card. International Journal of Computer Applications. 81, 12 ( November 2013), 24-28. DOI=10.5120/14065-2292
This paper elaborates the implementation of a PCI based device driver for a Data Acquisition System (DAS) Card using the RTDM (Real-Time Driver Model) skin over Xenomai kernel, which is integrated with the Linux kernel. A C language kernel module was written for the PCI bus based driver to provide hard real-time capabilities and determinism to any application accessing the DAS card. The PCI DAS card used consisted of 12-bit ADC, 12-bit DAC, Programmable Digital I/O lines (TTL compatible) and Timers/Counters. In order to test all the features of the DAS and the performance of the driver, a test system, consisting of a 3-axis analog accelerometer connected to the ADC of the DAS via a junction box and powered by its DAC, was been constructed. Additionally, a 3-axis digital accelerometer communicated with an AVR development board via I2C in order to generate conditioned input for the programmable digital I/O lines of the DAS card. A graphical tilt measurement application involving real time acquisition of the accelerometers data was implemented using OpenGL. Finally, the driver was thoroughly tested with this arrangement, and the interrupt latencies were noted to be around 4µsec.