Once the test is completed and no errors are detected by the MCU (microprocessor unit), then the infusion system is ready to be programmed by the user for use on a patient.
The On Chip RAM and the SDRAM contain all the information the pump needs to control such things such as flow rate and uniformity, and contains the controlling programs that tell the infusion system what to do in situation where errors are detected. Alarms are signaled and controlled by the interaction of the different memory locations the External Peripherals Interfaces. Settings stored in the MCU that set off the alarms detect things such as back-flow, line occlusion, improper line priming, and even needing to change the syringe.
All actions performed by the infusion system flow through the microprocessor. After the initial boot-up, settings are entered in by use of the keypad. That information is received and processed through the MCU’s System Controls PRCM (power, reset, and clock management) and sent to the General Purpose Memory Controller. There, the entered settings are stored until they are no longer needed. External Peripheral Interfaces control the display settings, the output devices, and of course the pump itself (Figure 1-4). There are other features of the processor that control optional input/output devices, graphics accelerator and display processors.
It is easy to see how much the microprocessor affects medical devices. Other devices, by use
of the microprocessor, can actually store and monitor a patients history and makes adjustments to the settings automatically. Or also have features such as talk-to-text for the sight impaired. Medical devices are increasingly efficient to the point that they nearly function on their own. Although the use of microprocessors is used largely for communication and entertainment, the use of them in medical devices is saving lives in increasing numbers all over the world.
References
1.Korneev, V. V., and A. Kiselev. "Chapter 1 Modern Microprocessors and Chapter 2 Universal Microprocessor." Modern Microprocessors. Third ed. Hingham, MA: Charles River Media, 2004. Print.
2."Medical Applications Guide." Http://www.ti.com/lit/sg/slyb108e/slyb108e.pdf. Texas Instrument, 2010. Web. <http://www.ti.com/lit/sg/slyb108e/slyb108e.pdf>.
3. "Texas Instruments AM3517 Sitara ARM® MPU." Mouser Electronics - Electronic Component Distributor. Web. 22 Nov. 2011. <http://www.mouser.com/tisitara/>.
Fig 3
Fig 4