mi mi / Mbed 2 deprecated wave_player_super_lite

16bit resolution PWM wave player with SD card, super lite version.

Dependencies:   mbed DirectSPI FastPWM

Supported boards (confirmed):
Nucleo-F030R8
Nucleo-L152RE
Nucleo-F401RE
Nucleo-F411RE

Only compilation is OK (unchecked, but may work):
Nucleo-L073RZ
Nucleo-F334R8
Nucleo-F303RE
Nucleo-F429ZI
Nucleo-F446RE
Nucleo-F446ZE
Nucleo-L476RG

Supported SD card:
SDSC/SDHC card,
FAT16 and FAT32.
(1) At first, format SD card using SD Card Formatter
https://www.sdcard.org/downloads/formatter_4/index.html
(2) Copy PCM wav files to the SD card.
Supported file:
PCM wave file that have file extension ".wav" on root directory.
16bit/8bit, fs(sampling rate)=32kHz,44.1kHz,48kHz.
Stereo/Mono.

Hardware setting:
Refer to the file port_setting.txt
PWM output port:
Left upper(Hi) PWM 8bit out: PB_5 (TM3_CH2)
Right upper(Hi) PWM 8bit out: PB4 (TM3_CH1)
Left lower(Low) PWM 8bit out: PC_9 (TM3_CH4)
Right lower(Low) PWM 8bit out: PC_8 (TM3_CH3)

USER_BUTTON: PC_13(default button)
Next song: One click in Play mode.
Pause : Push long time .
Play : One click from Pause.

--- a/main.cpp	Sat Jan 19 19:44:33 2019 +0900
+++ b/main.cpp	Mon Jan 21 22:17:25 2019 +0900
@@ -33,12 +33,12 @@
  --------------/
  */
 
-#if UART_INFO
+#if UART_INFO && DEVICE_SERIAL
 Serial pc(USBTX,USBRX);
 #endif
 
 int main() {
-#if UART_INFO
+#if UART_INFO && DEVICE_SERIAL
     setbuf(stdout,0);
     pc.baud(115200);
 #endif
@@ -50,3 +50,4 @@
 }
 
 
+void error(const char* format, ...) { }