Transcript ECE 300
ECE 300 Microprocessor Project Group 6 Group Members Corey Wingate (Team Leader) Eugene Vasser Jason Nitzberg Johnathan Carter Presentation Outline Project Objectives The MSP 430F449PZ Controller Board Construction MSP 430 chip SM components (capacitors, resistors) JTAG connector LCD Display Presentation Outline Banana Jacks Standoffs Flashing the Board Interfacing the Sensor Project Objectives The main objective was to build a circuit board with the microcomputer on-board. From this, many smaller objectives were satisfied: Members gained experience as a team. Members learned the layout of a printed circuit board. Experience with soldering small components was developed. Project Objectives Some C programming experience was gained. Members learned about various sensors and their characteristics. Experience with interfacing a sensor with the microcomputer was gained. MSP 430F449PZ Controller Physical Characteristics The microcomputer is a very fine-pitch chip. 25 connect points cover one side of the chip. The chip is about ½ inch on each side. MSP 430F449PZ Controller Due to these physical characteristics, the soldering was expected to be tedious. Fortunately, a microscope and soldering kit was provided to all teams in order to aid in making the fine connections. Board Construction The parts to make the board were obtained from the Ferris Hall Parts Store for $15. After acquiring the kit, members were encouraged to practice soldering. Once this experience was gained, the smaller surface mounted components were started. Board Construction All of the capacitors were placed corresponding with the lettering on the board: C1 0.1 uf C2 0.1 uf C3 10 uf (polarized) C4 0.1 uf C5 0.1 uf Board Construction C6 10 uf (polarized) C9 1.0 uf C10 0.1 uf To avoid complicating the placement of the JTAG, SM components were soldered near it before the JTAG was put in place. Once this was done, the chip itself was placed, then the LCD along with the push button, crystal, standoffs, etc. Board Construction As expected, the chip proved to be the hardest soldering of all. To facilitate the process, the edge pins were soldered first in order to maintain the proper alignment along the board traces. After that, pins were soldered in alternating order, working near the top then switching to the bottom. This allowed part of the chip to cool down while another pin could be completed. Flashing the Board After the board construction was completed, it was time to test out the chip. To do this, the files provided on the course website were used along with the software that came with the Texas Instruments kit. Using files delay.c, demo.c, and lcd.c, the message “8880888” was scrolled across the board. Flashing the Board Fortunately, the message displayed without any irregularities in the LCD screen. The only trouble with the board came about in hooking up the JTAG connector. At first, the connector was inserted upside down, preventing any communication with the board. This was quickly detected, though, and it was determined the board was functioning correctly. Interfacing the Sensor Once the test message had been implemented, the next and final step was to interface the sensor. An AD22103 model temperature sensor from http://www.analog.com was used. The file sensor.c provided on the course website was used as the foundation for the board communicating with the sensor. Interfacing the Sensor The physical aspects of the sensor were fairly simple, as shown in the following diagram: GND pin is on the left. The middle pin is voltage out. And the right pin is where the source voltage for the sensor comes in. Interfacing the Sensor Once the pins were identified, the sensor was hooked directly to the board. Using delay.c, lcd.c, and sensor.c, the board was able to communicate and display the sensor reading. Adjustments to sensor.c allowed us to manipulate this output until the proper temperature was displayed. Interfacing the Sensor The definition for the variable “sample” was the only modification necessary. The correction factor was manipulated until the output displayed the correct temperature. Summary / Things Learned Soldering is hard! All of us learned circuit troubleshooting, logic troubleshooting in the compiling process, and the value of a thorough test. Be super vigilant about doing things way ahead of time. “Putting things off” always hurts you in the end.