Algorithm Scheduling

2087 WordsApr 22, 20129 Pages
REAL TIME AND EMBEDDED SYSTEMS [ECWM611] Coursework 1: Report Submitted by: Louis Thompson TASK 1 (A) An embedded system contains the following independent software tasks: Control: The system performs closed-loop control of a robot. Loop processing takes 10 milliseconds. Alarm monitoring: A set of 5 alarm sensors are connected to the processor via a slow speed serial link. Each individual monitoring transaction (per alarm point) takes 10 milliseconds. It is assumed that all points are scanned in sequence. Display driving: A standard monitor is used to display system status to an operator. The display subsystem has a dedicated graphics board. It takes a maximum of 20 milliseconds to update the display information.…show more content…
In order to configure the timer a few values needed to be set and calculated the first value to be considered was the TMR value (appendix TMR) the tmr is a 16 bit register whose first 8 bits will represent the value of the prescaler which can range from 1 to 256 (appendix: Prescaler) and whose last 8 bits form a control mechanism for the tmr see below /************************************************************************** Section 6.3.11 of the MC68307 USER’S MANUAL CE1–CE0—Capture Edge and Enable Interrupt 00 = Disable interrupt on capture event  01 = Capture on rising edge only and enable interrupt on capture event 10 = Capture on falling edge only and enable interrupt on capture event 11 = Capture on any edge and enable interrupt on capture event OM—Output Mode 0 = Active-low pulse for one CLKO clock cycle (60ns at 16.67 MHz) 1 = Toggle output ORI—Output Reference Interrupt Enable 0 = Disable interrupt for reference reached (does not affect interrupt on capture func- tion) 1 = Enable interrupt upon reaching the reference value FRR—Free Run/Restart 0 = Free run: timer count continues to increment after the reference value is reached. 1 = Restart: timer count is reset immediately after the reference value is reached. ICLK1–ICLK0—Input Clock Source for the Timer 00 = Stop count  01 = Master system