7/29/2019 Elec 3040 Midterm Report

1/2

Jack Gray ELEC3040: Digital Design Lab (Profs Nelson and Hung ): Midterm Report March 1, 2013

Subject

During Lab 3, the goals were to use have LEDs count sequentially, and to make the LEDs increment fromzero to nine or decrement from nine to zero at a rate of one bit per second. CodeWarrior was used to createthe appropriate code that was loaded to the DragonFly chip.

Test ProcedureAfter creating a rough draft of the code, the DragonFly chip was wired to the EEBOARD according to Table1. Once the DragonFly was correctly wired to the EEBOARD, some corrections had to be made so switchone and two would be displayed on the LEDs. These were used to control if the LEDs were incrementingor decrementing. Once the direction could be controlled, the LEDs had to change at a rate of one bit persecond.

Figure 1: Connections from Circuit to EEBoard Digital Block

Observations

Once the code was loaded to the DragonFly chip and the chip was activated, the LEDs incremented fromzero to nine and then recycled continuously. The LEDs were connected to the Logic Analyzer according toTable 1. In Figure 1, the LEDs can be seen on DIO 8-11. This was relatively hard to keep count on so an

adjustment had to be made.

Figure 2: Incrementing LEDs Not Showing Count

In Figure 3, the LEDs were combined to make a bus so that the count could be easily read while usingthe single run button. Figure 3 shows the LEDs at the end of the incrimination cycle and beginning thenext cycle. The LEDs could also decrement depending on the conguration of switch one and two.

Page 1 of 2

7/29/2019 Elec 3040 Midterm Report

2/2

Jack Gray ELEC3040: Digital Design Lab (Profs Nelson and Hung ): Midterm Report March 1, 2013

Figure 3: Incrementing LEDs Showing Count

The rate at which the LEDs changed could be read on the bottom of Figures 2 and 3. It was read to beabout 500ms or half a second. In order to get the count to change every second, the rst bit, DIO 8, waswired to the oscilloscope and the rate at which it changed was observed. It initially changed about everyhalf second. In order to get LED count to change every second, the delay had to be increased. This tookmultiple trials to get the one second change rate. The LED one second change rate can be seen in Figure 4.

Figure 4: LED Rate of Change

Conclusion

Initially getting the LEDs to display and count in consecutive order was relatively challenging. This waseasily converted over to show the incrimination of the LEDs by creating the Bus. The last part of gettingthe bit change rate to one second simply involved changing the delay. From these different little projects,the LEDs were shown to change at a rate of one second and could increment or decrement.

Works CitedELEC 3040 Lab Manual LAB 3 System analysis and Debugging with Oscilloscope and Logic Analyzer

Page 2 of 2