sayanee / belle Goto Github PK

I'm a little confused. When you press the button. It pulls the line low. Which means, after the Schmidt inverter, it's going to be high. Generally, reset pins are active​ low. I'm not sure about the esp though. And Your speaker logic is inverted. When the button is pressed, the output of the Schmidt trigger is high, so the speaker sees 3.3V at both pins. So it won't sound. And it will always beep when not pressed

Actual result

Truth table

Expected result

Truth table

Steps to reproduce

1. Wire up an ESP12F module (taking reference from Huzzah schematic)

   • GND to 0V
   • GPIO15 to 0V via a 10kΩ resistor
   • GPIO2 to 3V3 via a 10kΩ resistor
   • GPIO0 to 0V via a 10kΩ resistor
   • GPIORX to TX on serial
   • GPIOTX to RX on serial
   • VCC to 3V3
   • CHPD to 3V3
   • RST the chip by connecting rest to 0V briefly before flashing
     

2. Connect to the MacBook via the serial console cable

3. Open up Arduino IDE to flash a blinky program

   void setup() {
     pinMode(LED_BUILTIN, OUTPUT);
   }
   
   void loop() {
     digitalWrite(LED_BUILTIN, LOW);                   
     delay(1000);                   
     digitalWrite(LED_BUILTIN, HIGH);
     delay(2000);
   }

   

Actual result

1. Turn on the serial monitor
2. Reset ESP12
3. Upload the program
4. Arduino is having an error when flashing

Expected result

1. Turn on the serial monitor in Arduino IDE
2. Reset ESP12
3. Serial monitor should show waiting for download
4. Arduino should be successful in flashing the blinky progam

one thing needs attention is if 74HC14 is able to sink enough current from the buzz. From datasheet the buzz max need 30mA, 74HC has max in/out current of 25mA, a bit tight

use a small resistor to isolate. because the speaker may create some nasty spikes

When U1 output low, buzzer is turned on. Is R4 10K too large?

when button is pressed, U1 output low, buzz turn on, the potential at right side of R4 is not low enough to bring ESP into reset

Ensure the correct layers are picked during gerber generation. Right now, the top silkscreen layer looks like this. Things like V1.0 didn't show up.

Another option is to move text you want in the silkscreen to the silkscreen layer.

and stop all confusions

1. R3 can be rotated 90 degrees and placed between M3 mounting hole and buzzer.

This would aid soldering of ESP-12 pads and makes any reworking easier.

2. Board information can be moved upwards to avoid last "e" in sayanee from overlapping with via

3. M3 label can be placed nearer to NTPH holes

4. Via is too closed to bottom trace (blue arrow)

5. There seems to be an issue with the top copper pour set to "+3v3"?

Usually the planes are tied to ground instead of a voltage, unless you are working with >2 layer boards where a layer is required to connect components to 3v3/5v.

If this is switched, there will be lesser vias with R4, C1, R1, C4, C7, C3, C6, C2 all having one side of the pad connected to the ground plane directly.

Is P3 configured to any of your usual USB-Serial adapters pinout?

standard from dfrobot

I don't understand what you're trying to make of the speaker, it's connected to the REST (reset?) line. Did that work in your prototype?

Related to the position of mounting holes in the future #10

soldering

Is the esp module going to be soldered on the board or headers will be used! I have seen cases where the antennas failed to worked when radio modules are soldered on like an SMT with a no copper area. More considerations will be required if the module is soldered on directly.

position

it'd be nice if ESP12 antenna was right up to edge of your PCB with some copper clearance (5mm) to left&right&top&underneath of antenna pattern. And pls move the R5 away from the antenna.

a small problem in the PCB. Via's diameter is too small. Typical board house will need 0.15mm on both sides of the hole, so minimum you need via size = hole size + 0.3mm

put a 0Ω resistor so that the same PCB layout can be used for both 3AA with LDO and 2AA without LDO

1. Solder wire from PCB's battery wire connectors to the battery holder
2. Screw PCB and battery holder onto the acrylic sheet
3. Attach an acrylic sheet to the wall with 3m Mushroom Dual Lock Self Adhesive Tape

values

your decoup caps C2 C3 C4 -- i know these are the datasheets' basic recommendations, but it doesn't hurt to make them slightly larger, especially this is a "one-off" prototype you're building. It'd be nice if C4 is 47-100uF, and C2 is 47uF. It's just a feeling 'cos ppl have issues during the early prototypes around the esp8266.

add more capacitors:

1. AP2112 pin OUT and pin IN with additional 1nF
2. ESP pin VCC with additional 1nF

• dimension of 3 AA battery holder: 4.5cm by 5.8cm
• proposed dimension of the PCB: 4.5cm by 4.5cm
• antenna position is external to the PCB (example)

R3 can probably be between buzzer and the m3 hole. Makes it easier for the iron tip to reach the esp12 pads if rework is needed.

https://www.adafruit.com/product/2491

• move the bell connector right to the edge
• move the battery connecter to the edge
• layout component next to each other similar to the schematic
  • for debugging
  • for shorter traces
• add silkscreen with url and version
• label bell connector and battery connector pins
• label flashing connector pins