An architecture for adaptive real time communication with embedded devices

The virtual testbed is designed to be a cost-effective rapid development environment as well as a teaching tool for embedded systems. Teaching and development of embedded systems otherwise requires dedicated real time operating systems and costly infrastructure for hardware simulation. Writing control software for embedded systems with such a setup takes prolonged development cycles. Moreover, actual hardware may get damaged while writing the control software. On the contrary, in a virtual testbed environment, a simulator running on the host machine is used instead of the actual hardware, which then interacts with an embedded processor through serial communication. This hardware-in-the-loop setup reduces development time drastically but is reliable only if it behaves as close to real time as possible. Use of non-real time architecture like Windows NT on the host machine and the Win32 API causes an overhead in the serial communication that slows down the simulator. The problem is that the simulator is unable to cope with the communication speeds offered by the embedded processor. We propose the development of a kernel mode device driver that overcomes inefficiencies in the Win32 API. The result is faster communication between the simulator and the embedded processor. Another problem that arises with an increase in the simulator’s communication capabilities is whether the operating system can support such a dynamic and high speed interaction. To solve this problem we propose the use of efficient process and thread management and utilization of Windows NT’s support for real time execution and utilization of intelligent buffer and interrupt handling to process the high frequency requests coming from the embedded processor to the host machine. Another hurdle is the diverse nature of hardware that is being simulated: from simple features with low data volume to fairly complex features with high data volume, and with the data rate ranging from very small to very high. Hence, we propose to make the simulator and the kernel mode device driver adaptive. All these strategies culminate into an architecture for adaptive real time communication with the embedded processor, giving the virtual testbed an edge over other design methodologies for embedded systems

Development and Characterization of An Injury-free Model of Functional Pain in Rats by Exposure to Red Light

We report the development and characterization of a novel, injury-free rat model in which nociceptive sensitization after red light is observed in multiple body areas reminiscent of widespread pain in functional pain syndromes. Rats were exposed to red light-emitting diodes (RLED) (LEDs, 660 nm) at an intensity of 50 Lux for 8 hours daily for 5 days resulting in time- and dose-dependent thermal hyperalgesia and mechanical allodynia in both male and female rats. Females showed an earlier onset of mechanical allodynia than males. The pronociceptive effects of RLED were mediated through the visual system. RLED-induced thermal hyperalgesia and mechanical allodynia were reversed with medications commonly used for widespread pain, including gabapentin, tricyclic antidepressants, serotonin/norepinephrine reuptake inhibitors, and nonsteroidal anti-inflammatory drugs. Acetaminophen failed to reverse the RLED induced hypersensitivity. The hyperalgesic effects of RLED were blocked when bicuculline, a gamma-aminobutyric acid-A receptor antagonist, was administered into the rostra! ventromedial medulla, suggesting a role for increased descending facilitation in the pain pathway. Key experiments were subjected to a replication study with randomization, investigator blinding, inclusion of all data, and high levels of statistical rigor. RLED-induced thermal hyperalgesia and mechanical allodynia without injury offers a novel injury-free rodent model useful for the study of functional pain syndromes with widespread pain. RLED exposure also emphasizes the different biological effects of different colors of light exposure. Perspective: This study demonstrates the effect of light exposure on nociceptive thresholds. These biological effects of red LED add evidence to the emerging understanding of the biological effects of light of different colors in animals and humans. Understanding the underlying biology of red light-induced widespread pain may offer insights into functional pain states. (C) 2019 by the American Pain SocietyNational Center for Complementary and Alternative Health [R01AT009716]; National Institute for Neurological Disorders and StrokeUnited States Department of Health & Human ServicesNational Institutes of Health (NIH) - USANIH National Institute of Neurological Disorders & Stroke (NINDS) [1R01N5098772]; NINDSUnited States Department of Health & Human ServicesNational Institutes of Health (NIH) - USANIH National Institute of Neurological Disorders & Stroke (NINDS); Children's Tumor Foundation; University of Arizona12 month embargo; published online: 2 May 2019This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]