Hardware Bring-Up

[1] PCB circuit

A. Open-Short Test

   Open state for between the Vcc-pin and GND-pin is good.

B. Powered Circurity Electric Operation

-Regulator Circuit

 Check about correct voltage input and output operation. If there are

 unexpected situation, check datasheet, parts orientation and extra circuit

 for making wrong values. test with a multimeter or check temperature

 on powered or smell if burn-out.

 ** In powered test, I've got some smell and feel the heat of one LM2940 IC

    on back of PCB side also there are voltage goes to 0V and found the short

    the V-out pin of one LM2940 circuit to the other GND pin of LM2940.  

    , so I plug out quickly power adapter(DC12V out).

    And check about below.  

1. Extra component makes wrong voltage output.

  *1. one module output voltage to 1.4V dc cause of extra cap, also it

      makes heating LM2940 IC (12V DC input voltage drop down to 1.4V,

      the amount of difference voltage makes heat).

      -> remove the extra diode to make right operation.

 2. Predefined cap circuit trouble.

  *1. Check the datasheet of LM2940 and fabacademy records, and find

      a result to resonable value of capacitors for between V-in, V-out

      pins to GND. (1uF for V-in -> GND, 10uF for V-out->GND, no polarity

  *2. Fix it : I checked about the voltages through the external circuit test.

      Also apply to Audio Selector, test the values and find correct status.  

-I2C LCD Power Test

   ** Power On state is good.

- MCU identification

   ** Unstable identification

     - Fabisp - avrdude check : sometimes found but next time id goto 0

     - AVRMKII - atmelstudio7 :  'device Programming' icon menu run ->

       not read id.

   *1. mcu soldering error

   *2. VCC pins(4,6) not pull to +5V(floating-schematic error), AVCC,AREF

       pin link to GND via 100nF capacitors, need to pull +5V.    

[2]  Firmware Bring-up

A. Arduino Bootloader on Audio Selector(Atmega328P)

    arduino firmware(optiboot_atmega328.hex) download in AtmelStudio7

    via AVRISP MKII. Together fuse set(EXTENDED : 0xFD, HIGH:0xDE, LOW:0xFF).

B. I2C protocol implementation both Audio Selector and I2C LCD module

C. Encode menu control on Audio Selector

D. Analog Audio Mux control on Audio Selector

E. VU-Meter and Speaker Test

F. Sound Select Test

G. LED Ambient light test