Assignment 06 — Computer Controlled Machining

08. OUTPUT DEVICES

GROUP WORK

Softwares: KiCAD, ArudinoIDE
Devices: Xiao RP2040, MCFR522 Reader, TLC (?) Oled
Files: 7.RFIDReader.ino 8.TarotPRogrammer.ino, 8.TarotGuideElectronicPrototype.ino
ChatGPT: RFID Scanner Code Prompts

PCB TROUBLESHOOTING PRT 3

RFID UID PULL UP CODE

TAROT MEANING CARD ENCRIPTION

NFC ENCRYPTION DISPLAY ISSUES

FINAL TAROT GUIDE ELECTRONICS PROTOTYPE

SPEAKER AND AUDIO AMPLIFIER (rip)

I fried my Xiao for the 3rd (THIRD) time last week after class so I was back to the drawing board to trouble shoot what was wrong with my board. Anthony gave me advice to tape the bottom of my Xiao and to to use pull up resistors onto my board. I also consulted ChatGPT which recommended adding two capacitors to my RFID reader to help with the signal. I used a 10uF and .1uF capacitors in series.

This time around I also finally added text to my board

Then it was onto my next victim... this time luckily taped!

I used my “RFID UID Pull Up” code from last week, to test if my RFID reader worked (it did!!), but I did notice the range to can the cards had decreased.

Reworked my code from last week that I used to write the meanings onto the NFC tags, only this time instead of manually changing each card one by one using “writeTagMessage(“”)”, I just had them pasting the tarot card meanings in sequence when holding the button. And it identifies NFC tags, including ones with no stored messages, and when I press the button 3 times it changes to the next card meaning to paste.

Hermit Meaning and Empty Card Identification

Duplicate Messages: NFC Card data is not wiped before pasting in new information

At first, I worried that these errors were because of the display module, but then I remembered that maybe the issue is with the NFC card storage! Each tag can oly store store up to 504 Bytes of memory which was probably much less than the small phrases I was attempting to save.

Thinking of a workaway around this, I realized I could store the written information in my code instead of on the individual NFC tags, using each cards unique UID instead to identify which card it is and its meaning. So I began logging each card’s UID tag using my serial monitor and rewrote my code.

I also added a screen scroll feature so you can read the text as it passes by. and it finally worked!! Each card has a unique meaning and name tied to its UID tag.

I also tried using an Audio amplifier and speaker to potentially speak out the meanings instead, but when tried to test out a little dial tone code I realize I soldered the piece BACKWARDS and it didn’t work...

and then when I tried removing it, tragedy struck and it ended up tearing out despite how gentle I was being... ;-;

NFC Card storing gibberish after the first swipe

LESSONS LEARNED

Milling out my board has gotten pretty easy!! but I need to pay more attention to my placement of pieces... the mistake with the audio amplifier couldve been avoided if I had my PCB editor up as I soldered...
504 bytes of information is not a lot of space... working around storage issues by only using UID IDs is probably the direction i will go for my final piece
Using the small parts is important for the entire board!! I haven’t actually used any resistors or capacitors other than the zero ohm resistor besides this week, but the impact is noticeable on the way my RFID reader is now working!