The following prototype was designed in accordance to Week 6's final project presentation. It must be noted that there were some slight adjustments to the power supply. I'm under the impression that the utilization of breadboards within this setup are causing powering issues, in addition to extra noise.
I'm intending to transfer the circuit components to perfboards within the near future.
Other (prototyping purposes)
For this week, we students were tasked to create a prototype of our final project. While I intended to finish this assignment, I ran into technical issues due to the nature of the project.
Specifically, supplying power to my synthesizer has been challenging throughout my process. For the utilized integrated circuits (osc and filter), negative voltage (-15v), positive voltage (+15v), and ground needed to be properly handled for functionality purposes. Furthemore, I'm finding that managing these feeds is essential within the troubleshooting area.
I'm currently under the impression that amperage drops within the breadboard connections might be the cause of this issue, as a slight increase from 5 milliamps to 8 milliamps in one of the power supplies (-) resolved the connection between the single oscillator module's output and filter module's input.
In a related matter, I carelessly overlooked the final output of the system, where a direct connection to my headphones dropped the supplied power, causing the setup to not function. An additional discrete 5v supply from an arduino, utilized in conjuction with an audio amplifier, resolved the issue. It must be noted that this 5v supply was also utilized for the oscillator's frequency control voltage.
The following video displays the current setup:
By the end of next week, I'm hoping to add the additional oscillator, implement the summing amplifier (oscillator summing) via op amp, and source the additional 5v from the main power supply. I'm under the impression that the additional oscillator might be the biggest hurdle due to the power issue. If I'm unable to implement this component within the system, I'm intending to replace it with another synthesizer component, possibly pertaining to the manipulation of the first oscillator's control voltage.
As our class has temporarily become online only, we students were asked to submit a video presentation regarding our proposed final project.
Slides per request:
For class, we students recieved information pertaining to basic electronics, pertaining to the theory and components. Additionally, we were instructed to begin brainstorming ideas for our final project. We students will present our ideas in the following class.
For our fourth week of class, we students were tasked to complete our individual letters for the class marquee sign project. As we students had finished the design of our circuit and board layout, milling the circuit board, soldering the components, and uploading the code were on the plate.
Regarding project files, the following download links contain the finalized elements:
As the virtual design of my letter had been completed the prior week, I began the remainder of this project with the OtherMill. Upon interfacing my laptop with the mill, I set the appropriate parameters for the process, entailing board dimensions, bit selection, and base plate configuration. Thereafter, the milling commenced.
After finishing my letter and discussing the process with a fellow classmate, I unfortunately designed the wrong letter. Hence, it was necessary to redesign the circuit for the proper letter. Upon finishing the redesign, milling commenced... again.
After beep-testing the circuit for proper continuity, I began gathering the surface mountable components and solder paste for board application.
Upon attempting to apply the paste with a thumb tack, I began having difficulty regarding the proper placement on the solder locations. This was due to the small form of the circuit board. To alleviate this situation, I decided to utilize the provided stensil instructions.
After finishing the stensil, solder paste was applied to the board. Thereafter, all components were added to the piece with a pair of tweezers. Upon finishing this step, the board was placed on the coffee mug heater for a couple minutes, followed with the utilization of a heat gun (260 degrees) to melt the solder.
Upon confirming the proper installation of the soldered components with beep testing, I began the programming process with a ATTiny85 and mirrored circuit board layout within a breadboard.
After finalizing the programming, solid core wires were soldered to the circuit board for both the ATTiny85 and capacitive sensor. Thereafter, the the former's wires were connected to an Arduino UNO for bootloader flashing, followed with the microcontroller programming.
Upon successfully loading the program to the ATTiny85, I tested the sensor (capacitive sensor) for the animation triggering.
While the sensor's exposed wire provided a means interacting with the controller, the weight and physical handling of this wire caused the copper trace to lift off the board. Unfortunately, I was forced to remove this wire, as I did not care to further damage the board. However, it must be noted that the sensor still works through the touching of the leftover solder.
While I was primarily content with my first attempt at designing a circuit board, the unfortunate, mentioned sensor issue at the end of this project caused a slight damper. With that said, any future iterations of this work will be handled in a manner where this sensor is designed with a strong, stable characteristic.
Within our third week of class, we students were introduced and granted instruction pertaining to the PCB design software Eagle. Futhermore, we began the creation of our circuits for the Marquee sign class project, where each student creates a circuit for their assigned letter.
For this week's assignment, we were tasked to finish our letter creation, abiding to the provided guidelines. The following links contain the required project files:
As mentioned, the creation of my PCB marquee letter began within class lecture, as our Eagle tutorial was handled in conjunction with our assignmnet. And regarding this instruction, we were introduced to various tools within the software, particularly focussing on components and the connections between these components.
Upon finishing this particular design element in class, we began focussing on the board layout for our letters. To say the least, the initialized Eagle board setup for our circuit required some additional organization.
After a bit of effort...
...the finalized PCB design was finished.
It must be noted that the utilization of the layer menu, turning on and off components of the board, allowed for smoother navigation within the environment. Additionally, various rearrangements of the components allowed for a design without the utilization of "vias."
This second week pertained to information and the utilization of the ATtiny85 microcontroller. Within the class session, we students setup an Arduino Uno as an ISP to flash a bootloader to an ATtiny85. Thereafter, we uploaded additional code to the ATtiny85 in a similar manner to how we would normally program an Arduino.
Regarding our assigment, we students were tasked to develop an ATtiny85 jig, where we would utilize a perfboard directly connected to an Arduino Uno. Furthermore, we were also tasked to utilize this jig to program any interactive setup with this particular microcontroller.
As I cared to develop my jig in a manner directly reflective of the in-class lab, I began the process of mirroring the breadboard component connections to the perfboard. It must be noted that this approach pertained to the utilization of an LED, where I could quickly test if the ATtiny85 bootloader and programming instructions are functioning correctly.
To start, we aligned headers directly onto the Arduino Uno and soldered the perfboard on top of these headers. This approach allowed proper alignment of the necessary pins for the jig. Afterwards, the IC socket and ground cable were attached.
Thereafter, the power connection was handled.
This step-by-step processed continued, attaching all capacitors, resistors, and LED to each pin.
Upon finishing the soldering, I attached the jig onto the Arduino for testing. Regarding this testing, I followed this step-by-step process: set the IDE's board selection to an "Arduino Uno", load the "ArduinoISP example", upload the "ArduinoISP example" to the Uno, set the Programmer to "Arduino as ISP", set the IDE's board selection to "ATtiny25/45/85", set the clock to "8MHz", utilize the IDE's "Burn Bootloader" function, and finally, utilize the "Upload Using Programmer" function. Upon following this process, I successfully uploaded a quick blinking script to the ATtiny85.
ATTINY85 INTERACTIVE PROJECT
For the interactive project component of the assignment, I chose to program the ATtiny85 with a potentiometer and an array of LEDs, where the former would trigger the flashing rate of the latter. Additionally, I planned to utilize a 9 volt battery for the battery source, requiring the utilization of a voltage regulator.
To begin the process, I began soldering the LEDs and associative resistors (330 ohms) to a small perfboard. Additionally, I ran stripped solid core wire across the positive end of the LEDs (in parallel) and across the resistors to establish the ground. Afterwards, I attached the IC socket to the perfboard.
Thereafter, the grounding pin was connected to the LEDs' resistors' ground.
Then, the voltage regulator with heat sink, turning 9 volts to 5 volts, was attached to the perfboard. Within this process, the regulator's ground and output voltage were also established to their coordinating areas.
Next, the potentiometer was soldered to the perfboard, with the voltage-out connected to the associtive socket pin. Additionally, the connection between the IC socket pin and LED array connection was established.
Ground and power was then soldered to the potentiometer, followed with the connection between the 9 volt battery and the voltage regultor.
And after uploading the code for the flashing LEDs, controlled by a potentiometer, I was met with success. It must be noted that I the length of the 9 volt's cables were shortened prior to testing.
I was very surprised about the simple nature of programming a microcontroller through the utilization of an Arduino and its IDE. I am looking forward to future work within this area.
For our first week of class, we students immediately jumped into the handling and untilization of SMDs through the building of a battery charger. Additionally, we were asked to review both Arduino circuit board components and programming through provided web links.
BATTERY CHARGER PROCESS
To begin the construction of the USB charger, we gathered each independent component. Thereafter, we placed these components onto a double sided piece of tape and labeled each one for organizational purposes. It must be noted that the provided circuit board was milled by the instructor. In addition to these electronic components, we were provided both a pushpin and dollop of solder paste, where the former would be utilized to spread the latter onto the circuit for soldering.
Thereafter, we began the process of placing each component through the utilizaiton of prior mentioned technique. We first applied the solder paste to each area where the surface mounted component would be utilized. Then, we placed each piece onto the board, verifying the proper direction within the process. It must be noted that the IC for handling the charging process was not included in the prior work.
To handle the mentioned IC, we students utilized a Manncorp's SMT Place 2000 to manually place the component onto the board. Thereafter, we placed the assembled circuits onto a coffee warmer pad to bring the paste's flux to its melting point. Aftewards, a heating gun, set to 315 degrees, was utilized in a perpendicular manner to solder the components onto the board.
Upon finishing the last step, the board was tested with a rechargeable battery in conjuction with a USB power supply.
After reading both listed pages regarding the Arduino components and programming, I became extremely grateful for the previously taken ITP courses revolving around electronics (PComp and Electronics for Inventors). Furthermore, my computer science background also assisted with the digesting of the Arduino programming component.
With that said, my comfort level pertaining to the means of programming a new ATMega328p is rather low, as I have yet to partake in this activity. This issue specifically revolves around the protocols (SPI + UART) and the programming setups.