VSDSP Forum

What are the symptoms? Are you using fast-play (and sending all of the data), or skipping?

The vs1053b is rated at 55.3MHz. If you use a high internal clock for the vs1053, then also make sure your CVDD is both stable and high enough.

What kind of completely random errors you get? Are the functions returning error codes, or the data just ends up being garbage?

What do you read from SCI_AUDATA? If you get 0xac45, then the vs1053 probably is in real-time MIDI mode. When I start my program I pull the reset pin high, wait 50ms and then pull it low using digital write xRESET is active low, so there apparently is an inverter in the line of you have the high and...

Timeout and software reset should help. If the decoder stays stuck with DREQ high, what does HDAT1 contain? The mp3 decoder should not get stuck. If there are errors for other formats, there is a larger possibility of getting stuck. If the mp3 file contains an ID3v2 tag, then it may take a long whil...

For Real-Time MIDI latency, see: http://www.vsdsp-forum.com/phpbb/viewtopic.php?p=16081 You're right that the UART FIFO has a chance of being overrun with the ROM code when a lot of notes are active (but see the above for a patch). The MIDI decoder generates output in 64-sample blocks. Volume change...

What happens when we feeding the frame not from beginning but from the middle. The decoder finds the next location that looks like a mp3 header, then decodes and plays it. However, there is this "bit reservoir" option where the mp3 frame can reference data a the end of the previous frame....

There is a trade-off between easyness and error-freeness in jumping backwards in a mp3 file. The easy way is to just jump in the new location and let the decoder resynchronize. You will get some decoding errors. If you decode the mp3 headers yourself (the 4 first bytes contain all of the required da...

VS1053b reads whole mp3 frames, then decodes them (frame decoding cannot be interrupted, not even with SM_CANCEL), then plays the decoded audio. Decoding errors cannot generally be detected, there is no checksum and there are no "holes" in the code space, so the decoded frame is then simpl...

If you don't follow the mp3 frame boundaries, you will get decoding errors on the partial frames. (The vs1053b patches package tries to improve on this by adding a bit reservoir check, but it still won't be perfect.) vs1053 has a better way to fast-forward than skip some bytes (which is dependent on...

DAC and ADC can be used at the same time. However, I'm not sure what is the easiest way to do that with an external controller, i.e. without needing to develop an application for the vs1053b. I think you can first start the encoding mode (and set low volume for the monitoring path SCI_VOL=0xc0c0 and...