PCM Wave Player Super Lite with Nim language on STM32 MCUs.

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

Supported Board/MCU:

nulceo_f030r8
nucleo_l152re
nulceo_f401re
nulceo_f411re
STM32F0Discovery
STM32F3Discovery
STM32F4Discovery

Supported SD card:

SDSC/SDHC card,
FAT16 and FAT32.
(1) At first, format SD card with SD Card Formatter
https://www.sdcard.org/downloads/formatter_4/index.html
(2) Copy PCM wav files to the SD card on the root directory.

Supported PCM Format:

PCM wave file that have file extension ".wav" on root directory.
16bit/8bit, fs(sampling rate)=32kHz,44.1kHz,48kHz.
Stereo/Mono.

Defalut action:

Loop playback automatically and infinitly from power on.
USER_BUTTON on board operation: (PC_13 or PA0)
Next song: One click in Play mode.
Pause : Push long time .
Play : One click from Pause.

Hardware setting/Schematic: (16bit sound resolution)

Refer to the file, "port_setting.txt".
See folder doc/*

SD Card connection:

Pin side
 --------------\
         9     = \    DAT2/NC
             1 ===|   CS/DAT3    [CS]
             2 ===|   CMD/DI     [DI]
             3 ===|   VSS1
 Bottom      4 ===|   VDD
 View        5 ===|   CLK        [CLK]
             6 ===|   VSS2
             7 ===|   DO/DAT0    [DO]
         8       =|   DAT1/IRQ
 -----------------

                                         Arduino      NUCLEO-F411       NUCLEO-F030R8
 Logo side
 -----------------
         8       =|   DAT1/IRQ
             7 ===|   DO/DAT0    [DO]     D12           D12/PA_6           D12/PA_6
             6 ===|   VSS2
 Top         5 ===|   CLK        [CLK]    D13           D13/PA_5           D13/PA_5
 View        4 ===|   VDD
             3 ===|   VSS1
             2 ===|   CMD/DI     [DI]     D11           D11/PA_7           D11/PA_7
             1 ===|   CS/DAT3    [CS]     D8            D10/PB_6           D10/PB_6
         9     = /    DAT2/NC
 --------------/

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)

LED indicator:

See "port_setting.txt". If set up LED device to "LED indicator port", it will be dimmer during play mode (regular speed) and pause mode (fast speed).

Nim compiler:

Recomended nim compiler version is from 0.19.0 to 0.19.9 (2019-02-26) at this moment. (2019/10)
Nim verion 1.0 can't compile this project at this time due to the compilation error that I can't resolve it.

C compiler: arm-none-eabi-gcc:

v4.8.3 or later.
Recomend GNU Arm Embedded Toolchain (former Launchpad arm gcc)
or
GNU MCU Eclipse ARM Embedded GCC v8.2.1-1.4 20190214

Compiling source:

Example: (NUCLEO-L152RE board)

$ cd nucleo_l152re
$ nim -v
Nim Compiler Version 0.19.9 [Windows: i386]
Compiled at 2019-02-26
Copyright (c) 2006-2018 by Andreas Rumpf
$ arm-none-eabi-gcc -v
...
gcc version 8.2.1 20181213 (release) [gcc-8-branch revision 267074] (GNU MCU Eclipse ARM Embedded GCC, 32-bit)
$ make
Hint: used config file 'c:\nim-0.19.9\config\nim.cfg' [Conf]
Hint: used config file 'c:\wave_player_super_lite_stm32_nim\nim.cfg' [Conf]
Hint: system [Processing]
Hint: main [Processing]
Hint: conf_sys [Processing]
Hint: system [Processing]
Hint: stm32l152xe [Processing]
Hint: volatile [Processing]
Hint: reginfo [Processing]
Hint: reginfo_sub [Processing]
Hint: systick [Processing]
Hint: uart [Processing]
Hint: pwm [Processing]
Hint: gpio [Processing]
Hint: spi [Processing]
Hint: board [Processing]
Hint: sd_card [Processing]
Hint: wave_player_main [Processing]
Hint: fat_lib [Processing]
CC: main
CC: stdlib_system
CC: conf_sys
CC: system
CC: stm32l152xe
CC: stdlib_volatile
CC: reginfo
CC: reginfo_sub
CC: systick
CC: uart
CC: pwm
CC: gpio
CC: spi
CC: board
CC: sd_card
CC: wave_player_main
CC: fat_lib
Hint:  [Link]
Hint: operation successful (18766 lines compiled; 3.037 sec total; 16.488MiB peakmem; Release Build) [SuccessX]
    text    data     bss     dec     hex filename
    3420       0     112    3532     dcc BUILD/nucleo_l152re.elf

Generated files are,

BUILD/nucleo_l152re.bin
BUILD/nucleo_l152re.hex
You can just copy the bin file to mbed drive,
or can flash the hex file with ST-Link utility.

If you don't like to compile from source code, you can immediately flash doc/hex/*.hex or *.bin files.

Output music filename(now playing) through UART port.

By default music filename is send through default UART(USB-CDC(Nucleo boards)) port.

If you don't need UART output feature, set UART_INFO* = false in src/conf_sys.nim and
recompile the project.

Simple less bits mode:

If set PWM16BIT* = false in src/conf_sys.nim and recompile the project, simple less bits mode is enabled.
In spite of less parts, wirings and PCM bit length, it has fairly sound quality.

Table 1. Sound resolution in simple less bits mode

Board	Sound resolution	TIM_PWM_BASE_CLOCK
nulceo_f030r8	10bit	48MHz
nucleo_l152re	9bit	32MHz
nulceo_f401re	10bit	84MHz
nulceo_f411re	11bit	96MHz
STM32F0Discovery	10bit	48MHz
STM32F3Discovery	10bit	64MHz
STM32F4Discovery	10bit	84MHz

Pursue small code size:

In src/conf_sys.nim,by eliminating some functionalities, the code size can be further reduced.
For instance, set as follows:
UART_INFO* = false
PWM16BIT* = false ( set simple less bits mode)
DATA_8BIT_SUPPORT* = false ( only support PCM16bit format,neglect PCM8bit format)
HAVE_LED_IND_PWM* = false ( eliminate LED indicator function)
FS_48KHZ_QUP* = false ( only supoort less than fs=48KHz)
will result in about:

text    data     bss     dec     hex filename
2964       0     104    3068     bfc BUILD/nucleo_l152re.elf

In common.mk, uncomment and enable below option,
CFLAGS += -flto
and recompile project,

make clean
make

will result in about:

text    data     bss     dec     hex filename
2916       0     136    3052     bec BUILD/nucleo_l152re.elf

Now it can do auto playback after power on,
can operate play,pause and next song with push button,
be able to play fairly quality sound according to Table 1,
can recognize PCM 16bit wav file(but output quality is reduced accoding to Table 1.) and supports stereo/mono, fs=32KHz,44.1KHz.

References:

• PCM Wave Player Super Lite family
  • Nim: AVR Arduino Uno/Nano version is here. Completed.
  • Jalv2: PIC 16F1xxx version is here. Completed. Under construction.
  • C/C++: mbed version is here. Completed.