ESP8266 Community Forum

- Fri Jun 19, 2015 9:08 am #20923 Very cool project, especially because it doesn't need an external dac!

I'd expect rather poor sound quality though, as the pwm duty has only 8 bits resolution?

- Fri Jun 19, 2015 3:34 pm #20964 Here is a little video to show audio quality

https://youtu.be/jw8YRRStSrA

- Fri Jun 19, 2015 4:25 pm #20967

I'd expect rather poor sound quality though, as the pwm duty has only 8 bits resolution?

PWM_HACK = PWM 5 bits

- Fri Jun 19, 2015 7:55 pm #20994

Sprite_tm any progress for 512kb flash?

https://github.com/pvvx/mp3_decode
Support all ESP2866 modules (512 Kbytes flash)
Free Flash (512 Kbytes): 200 Kbytes. Free Heap: 20 Kbytes.
MP3-decodec-out uses IRAM Buffer > 20 Kbytes (IRAM: 48k + 16k cache Flash):

Code: Select allFlash Header:
Number of segments: 3
SPI Flash Interface: QIO
SPI CLK: 80MHz
Flash size: 512K
Entry point: 40100004
Segment 1: offset: 40100000, size: 27240
Segment 2: offset: 3ffe8000, size: 1704
Segment 3: offset: 3ffe86b0, size: 6588
Found free IRAM: base:40106a68, size:21912 bytes

Hardware initialized. Waiting for network.
mode : sta(18:fe:34:9f:c0:bf)
add if0
scandone
add 0
aid 2
cnt

connected with mns.ru-6446, channel 1
dhcp client start...
ip:192.168.1.50,mask:255.255.255.0,gw:192.168.1.1
Connecting to server 145.58.52.149...
Reading into SPI RAM FIFO...
MAD: Decoder start.
dec err 0x0101 (lost synchronization)
dec err 0x0101 (lost synchronization)
dec err 0x0235 (bad main_data_begin pointer)
dec err 0x0235 (bad main_data_begin pointer)
Rate 48000
Buffer fill 14096, DMA underrun ct 0, buff underrun ct 0
Buffer fill 21865, DMA underrun ct 0, buff underrun ct 0
Buffer fill 21889, DMA underrun ct 0, buff underrun ct 0
Buffer fill 21881, DMA underrun ct 0, buff underrun ct 0
Buffer fill 21857, DMA underrun ct 0, buff underrun ct 0
....

Doesn't work on my ESP-12, any ideas ?