Lee

SD card polyphonic sample player

125 posts in this topic

Hi, thanks for trying! It's a difficult one for me to comment on, as I don't have an STM core... There is one thing I'm wondering about, and that is how fast the SD card is being clocked. In order to maximise the transfer speed, I set the following in mios32_config.h:

#define MIOS32_SDCARD_SPI_PRESCALER MIOS32_SPI_PRESCALER_4

This makes it 30MHz for the LPC17 core (from the default clock divider of /8 which is 15MHz). However having checked the default speed for STM32 in the SD card modules, is is already at the divide by 4 speed - so I don't believe it can be the cause of the problem.

It could be another reason why the initialisation of the SD card is failing - anyone else out there able to help?

If you have your toolchain up, perhaps try recompiling the app with this after the current initialisation:

After this:

DEBUG_MSG("Initialising SD card..");

MIOS32_SDCARD_PowerOn();

Add:

MIOS32_SDCARD_Init(0);

This is how the card is initialised in the SD card troubleshooting example, so might help potentially. Like I say though, I don't have the STM32 to test it.

On another note, as the STM32 is slower you may get quite a bit less polyphony, so as the LPCs are cheap I'd recommend moving to this platform anyway if possible.

Cheers

Hey Lee,

I finally had the chance to give this a go. Thanks for all the work you've done! I haven't even come close to getting this far with my project! I'm using an STM32 core instead of the LPC core seeing as all I have is the STM. I seem to have run into some issues. I posted the debug message I got at startup after I uploaded the project.hex. Here it is:

[126248.098] Initialising SD card..

[126248.100] Opening config file player.cfg

[126248.100] [disk_initialize] error while checking for SD Card (status 0)

[126248.102] [disk_read] error while reading sector 0

[126248.104] [FILE] Failed to open root directory - error status: 1

[126248.104] Failed to open config file.

[126248.106] Opening bank file bank.1

[126248.106] [disk_initialize] error while checking for SD Card (status 0)

[126248.108] [disk_read] error while reading sector 0

[126248.108] [disk_initialize] error while checking for SD Card (status 0)

[126248.110] [disk_read] error while reading sector 0

[126248.110] [FILE] Failed to open root directory - error status: 1

[126248.112] Failed to open bank file.

[126248.114] Initialising synth...

[126248.114] Synth init done.

The SD card is formatted as FAT. I'm using a 1GB sd card, not sdhc or anything... I'm not sure if the issue is the fact that I'm using the STM32 or what is exactly going on... I know for a fact that the SD card reader and the core are talking as I've tested it all with the 'usb_mass_storage_device' app. Maybe the STM32 accesses the SD card in a different way? Any help is much appreciated!

Edited by Lee

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Sorry that we're no further forward on this, I have posted for debug help in the programmer's forum for someone with an STM32, but no takers so far...

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It took some minutes to debug this, but with some changes it's working now on the good old MBHP_CORE_STM32 module! :)

In mios32_config.h the SRIO port was re-assigned to J16 (for STM32 only), because J8/9 is used for I2S output.

Since J16 is allocated for SD Card, and since there is no other alternative available, SRIO is now disabled for STM32.

If you will ever create a control surface for this nice little synth, it would not work for STM32. But I think that this is acceptable...

Another issue was located in APP_Init(): The "SDCARD_PowerOn" sequence was only executed once, but the STM32 core needs some retries.

I don't want to spend too much effort into this (could be related to initial pin values after power-on), but it works after I added a "MIOS32_SDCARD_CheckAvailable()" loop, which internally calls SDCARD_PowerOn as well...

This is the intended power-up sequence anyhow (polling for SD Card), therefore we should let it like it is.

The changes are in the repository now.

I deleted the precompiled project.hex from the server, because the danger is too high that we are playing ping-pong with different binaries...

Btw.: max. polyphony on STM32 is 4 instead of 8 samples (sometimes 5 can be played in parallel...)

Best Regards, Thorsten.

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Thanks so much for your responses guys! When I get home, I'll test this out! Thanks for the debugging TK! I owe you a beer!

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Awesome, thanks TK! It needed some previous experience of SD card fun on STM32! :smile:

Is it ok if I re-upload a new hex file? Some of the guys like magneticstripper have had success with just the hex and a bank/config file, rather than needing a compile toolchain setting up?

Thanks again, you're a legend!

It took some minutes to debug this, but with some changes it's working now on the good old MBHP_CORE_STM32 module! :)

In mios32_config.h the SRIO port was re-assigned to J16 (for STM32 only), because J8/9 is used for I2S output.

Since J16 is allocated for SD Card, and since there is no other alternative available, SRIO is now disabled for STM32.

If you will ever create a control surface for this nice little synth, it would not work for STM32. But I think that this is acceptable...

Another issue was located in APP_Init(): The "SDCARD_PowerOn" sequence was only executed once, but the STM32 core needs some retries.

I don't want to spend too much effort into this (could be related to initial pin values after power-on), but it works after I added a "MIOS32_SDCARD_CheckAvailable()" loop, which internally calls SDCARD_PowerOn as well...

This is the intended power-up sequence anyhow (polling for SD Card), therefore we should let it like it is.

The changes are in the repository now.

I deleted the precompiled project.hex from the server, because the danger is too high that we are playing ping-pong with different binaries...

Btw.: max. polyphony on STM32 is 4 instead of 8 samples (sometimes 5 can be played in parallel...)

Best Regards, Thorsten.

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You're welcome! :)

Please rename the file so that it won't be overwritten when somebody else compiles the project inside the repository, because the danger is too high that a new (undefined) version will be uploaded on a "svn commit"

Proposal: create a "release/LPC1769" directory, and store the last tested project.hex file there (-> release/LPC1769/project.hex)

Best Regards, Thorsten.

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Done!

Buhler - please give the hex file a go in the release directory for STM32 and let us know how you get on. A tip (from help earlier today) - make sure that the config and bank files have Unix style new lines, this has caught a few people out. (TK - ideally we need to fix the FILE_ReadLine to work with DOS type files, but as it just inspects a character at a time it hits the carriage return, and the new line (\n) that follows gets processed as another line - couldn't think of a 30 second fix for now!).

Thanks everyone, Lee

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release/STM32 doesn't work, please use following settings:


export MIOS32_FAMILY=STM32F10x
export MIOS32_PROCESSOR=STM32F103RE
export MIOS32_BOARD=MBHP_CORE_STM32
export MIOS32_LCD=universal
[/code]

It's also important to execute "make clean" after environment variables have been changed, because there is no dependency check (means: files won't be recompiled)

Or better: create a release script for automated releases (automation is gold! :))

An example can be found here: http://svnmios.midibox.org/filedetails.php?repname=svn.mios32&path=%2Ftrunk%2Fapps%2Fsequencers%2Fmidibox_seq_v4%2Frelease.sh

(for your case: remove the check that breaks if the release directory already exists)

Concerning FILE_ReadLine(): I thought that it's already working for DOS style newlines... I won't have the time to check this before christmas

Best Regards, Thorsten.

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Whoops! I'd forgotten about that! I've rebuilt the STM version with the right environment settings and uploaded. Also taken the opportunity to clarify the project files and moved the examples for the SD card into their own folder!

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Magneticstripper: Do you know, i've only just noticed that the performance on your video ends when you rip the SD card out of the slot, lol - that is so funny!!!

Edited by Lee

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Hey Lee,

I've encountered somewhat of a bug in the bank switching. I plan to have a look at your code today to see if I can find the issue but basically, on a program change to any bank file other than 1, the app loads each sample twice. Here's the log from the MIOS output:

[687681.600] MIDI Program Change received - Changing bank to 2

[687681.600] Opening new sample bank

[687681.600] Opening bank file bank.2

[687681.602] Sample no 0, filename is: G1FLT.raw, midi note value=0x37, decay value 0, hold=0

[687681.604] Sample no 1, filename is: G1FLT.raw, midi note value=0x37, decay value 0, hold=0

[687681.606] Sample no 2, filename is: G#1FLT.raw, midi note value=0x38, decay value 0, hold=0

[687681.608] Sample no 3, filename is: G#1FLT.raw, midi note value=0x38, decay value 0, hold=0

[687681.610] Sample no 4, filename is: A1FLT.raw, midi note value=0x39, decay value 0, hold=0

[687681.612] Sample no 5, filename is: A1FLT.raw, midi note value=0x39, decay value 0, hold=0

[687681.612] Sample no 6, filename is: A#1FLT.raw, midi note value=0x3a, decay value 0, hold=0

[687681.614] Sample no 7, filename is: A#1FLT.raw, midi note value=0x3a, decay value 0, hold=0

[687681.616] Sample no 8, filename is: B1FLT.raw, midi note value=0x3b, decay value 0, hold=0

[687681.618] Sample no 9, filename is: B1FLT.raw, midi note value=0x3b, decay value 0, hold=0

[687681.620] Sample no 10, filename is: C2FLT.raw, midi note value=0x3c, decay value 0, hold=0

[687681.622] Sample no 11, filename is: C2FLT.raw, midi note value=0x3c, decay value 0, hold=0

[687681.624] Sample no 12, filename is: C#2FLT.raw, midi note value=0x3d, decay value 0, hold=0

[687681.626] Sample no 13, filename is: C#2FLT.raw, midi note value=0x3d, decay value 0, hold=0

[687681.628] Sample no 14, filename is: D2FLT.raw, midi note value=0x3e, decay value 0, hold=0

[687681.630] Sample no 15, filename is: D2FLT.raw, midi note value=0x3e, decay value 0, hold=0

[687681.632] Sample no 16, filename is: D#2FLT.raw, midi note value=0x3f, decay value 0, hold=0

[687681.634] Sample no 17, filename is: D#2FLT.raw, midi note value=0x3f, decay value 0, hold=0

[687681.636] Sample no 18, filename is: E2FLT.raw, midi note value=0x40, decay value 0, hold=0

[687681.638] Sample no 19, filename is: E2FLT.raw, midi note value=0x40, decay value 0, hold=0

[687681.640] Sample no 20, filename is: F2FLT.raw, midi note value=0x41, decay value 0, hold=0

[687681.642] Sample no 21, filename is: F2FLT.raw, midi note value=0x41, decay value 0, hold=0

[687681.644] Sample no 22, filename is: F#2FLT.raw, midi note value=0x42, decay value 0, hold=0

[687681.646] Sample no 23, filename is: F#2FLT.raw, midi note value=0x42, decay value 0, hold=0

[687681.648] Sample no 24, filename is: G2FLT.raw, midi note value=0x43, decay value 0, hold=0

[687681.648] Sample no 25, filename is: G2FLT.raw, midi note value=0x43, decay value 0, hold=0

[687681.650] Sample no 26, filename is: G#2FLT.raw, midi note value=0x44, decay value 0, hold=0

[687681.652] Sample no 27, filename is: G#2FLT.raw, midi note value=0x44, decay value 0, hold=0

[687681.654] Sample no 28, filename is: A2FLT.raw, midi note value=0x45, decay value 0, hold=0

[687681.656] Sample no 29, filename is: A2FLT.raw, midi note value=0x45, decay value 0, hold=0

[687681.658] Sample no 30, filename is: A#2FLT.raw, midi note value=0x46, decay value 0, hold=0

[687681.660] Sample no 31, filename is: A#2FLT.raw, midi note value=0x46, decay value 0, hold=0

[687681.662] Sample no 32, filename is: B2FLT.raw, midi note value=0x47, decay value 0, hold=0

[687681.664] Sample no 33, filename is: B2FLT.raw, midi note value=0x47, decay value 0, hold=0

[687681.666] Sample no 34, filename is: C3FLT.raw, midi note value=0x48, decay value 0, hold=0

[687681.668] Sample no 35, filename is: C3FLT.raw, midi note value=0x48, decay value 0, hold=0

[687681.670] Sample no 36, filename is: C#3FLT.raw, midi note value=0x49, decay value 0, hold=0

[687681.672] Sample no 37, filename is: C#3FLT.raw, midi note value=0x49, decay value 0, hold=0

[687681.674] Sample no 38, filename is: D3FLT.raw, midi note value=0x4a, decay value 0, hold=0

[687681.676] Sample no 39, filename is: D3FLT.raw, midi note value=0x4a, decay value 0, hold=0

[687681.678] Sample no 40, filename is: D#3FLT.raw, midi note value=0x4b, decay value 0, hold=0

[687681.680] Sample no 41, filename is: D#3FLT.raw, midi note value=0x4b, decay value 0, hold=0

[687681.682] Sample no 42, filename is: E3FLT.raw, midi note value=0x4c, decay value 0, hold=0

[687681.684] Sample no 43, filename is: E3FLT.raw, midi note value=0x4c, decay value 0, hold=0

[687681.686] Sample no 44, filename is: F3FLT.raw, midi note value=0x4d, decay value 0, hold=0

[687681.686] Sample no 45, filename is: F3FLT.raw, midi note value=0x4d, decay value 0, hold=0

[687681.688] Sample no 46, filename is: F#3FLT.raw, midi note value=0x4e, decay value 0, hold=0

[687681.690] Sample no 47, filename is: F#3FLT.raw, midi note value=0x4e, decay value 0, hold=0

[687681.692] Sample no 48, filename is: G3FLT.raw, midi note value=0x4f, decay value 0, hold=0

[687681.694] Sample no 49, filename is: G3FLT.raw, midi note value=0x4f, decay value 0, hold=0

[687681.696] Sample no 50, filename is: G#3FLT.raw, midi note value=0x50, decay value 0, hold=0

[687681.698] Sample no 51, filename is: G#3FLT.raw, midi note value=0x50, decay value 0, hold=0

[687681.700] Sample no 52, filename is: A3FLT.raw, midi note value=0x51, decay value 0, hold=0

[687681.702] Sample no 53, filename is: A3FLT.raw, midi note value=0x51, decay value 0, hold=0

[687681.704] Sample no 54, filename is: A#3FLT.raw, midi note value=0x52, decay value 0, hold=0

[687681.706] Sample no 55, filename is: A#3FLT.raw, midi note value=0x52, decay value 0, hold=0

[687681.708] Sample no 56, filename is: B3FLT.raw, midi note value=0x53, decay value 0, hold=0

[687681.710] Sample no 57, filename is: B3FLT.raw, midi note value=0x53, decay value 0, hold=0

[687681.712] Sample no 58, filename is: C4FLT.raw, midi note value=0x54, decay value 0, hold=0

[687681.714] Sample no 59, filename is: C4FLT.raw, midi note value=0x54, decay value 0, hold=0

[687681.716] Sample no 60, filename is: C#4FLT.raw, midi note value=0x55, decay value 0, hold=0

[687681.718] Sample no 61, filename is: C#4FLT.raw, midi note value=0x55, decay value 0, hold=0

[687681.720] Sample no 62, filename is: D4FLT.raw, midi note value=0x56, decay value 0, hold=0

[687681.722] Sample no 63, filename is: D4FLT.raw, midi note value=0x56, decay value 0, hold=0

I haven't figured out why this is happening. I'm not sure if it's something you've encountered before or maybe there's something other than the code that's causing the problem. I'll let you know if I find anything. Thanks again for your work on this project!

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Alright, I fixed it. It was my bank.2 file. Not sure why but I copy/pasted my bank.1 file(created on a Mac) while working in windows on something else, then I recreated it on the Mac side. Somehow, the data from the windows side screwed up the app and I had to redo the bank.2 file from scratch on my Mac! Word for the wise, don't create bank files in Windows! Not even '\n' could save me!

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Hi all,

I thought I'd share with you some pics of my pocket (well, large pocket) sample player build. It's got the regulator, midi interface and DAC under the LPC board to save space, and a headphone amp built in. The microSD is removable from outside, and you can see my 'quick and dirty' bank switch (on J10) as well as volume etc.

It runs from 4xAA batteries, with the headphone amp and DAC running from 6V (or whatever it can get, obviously fine on 5V from the USB if you power it from that) and the SD card, midi interface and LPC board from 3.3V. I haven't tested the battery life, but I'm expecting 8-10 hours.

It was hard to find a case of the approx right size, so the layout isn't really ideal and it's not very pretty, but it works, sounds ok and is ultimately very portable!

Cheers

Lee

post-10162-0-54906000-1326916740_thumb.j

post-10162-0-34399200-1326916751_thumb.j

post-10162-0-22101900-1326916759_thumb.j

post-10162-0-44096600-1326916765_thumb.j

post-10162-0-05503600-1326916771_thumb.j

post-10162-0-91364400-1326916778_thumb.j

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That is some very nice DIY!

I doubt, that you can take it in the handluggage of an aeroplane, though :)

Am waiting for a step-up converter to power the LPC with only 2 rechargable AA batteries, but yours will have a longer battery life-time!

Greets,

Peter

Edited by Hawkeye

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Sounds good, I'd be interested in the results of that, especially battery life and any noise from the conversion. As my board is only single sided, and with the DAC having a common power rail and ground (no digital and analogue) there is some digital noise, but it's not bad at all to be honest (I've heard worse on commercial devices!) :rolleyes:

Oh and in the pics before anyone mentions - there's no decoupling capacitors as they haven't arrived yet!! lol

That is some very nice DIY!

I doubt, that you can take it in the handluggage of an aeroplane, though :)

Am waiting for a step-up converter to power the LPC with only 2 rechargable AA batteries, but yours will have a longer battery life-time!

Greets,

Peter

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Looks nice, but as Hawkeye kind of inferred - try boarding an airplane with that thing and you'll see more of the inside of Gitmo than you want :hairy:

Still, I'm impressed by the compactness of the thing!

J

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Hi guys,

I was sent to this thread, as I think I'm looking for something like this. Please pardon my newbie ignorance-I have experience building audio gear - preamps, compressors, tube amps, etc, but I'm still pretty new with this type of stuff.

I built a Megadrum, and I use it to convert audio signals to Midifrom marimbas where I put piezos in the keys. Right now, the megadrum is feeding my computer via USB and I am using Reason synth sounds.

I'd like to build an onboard hardware sample solution on each marimba and ditch the computer. I was sent here, but I'm confused if the specs I need would work if I build this.

My soprano marimba has 21 keys. I want to sample each key with at least 4 layers of velocity:

21 x 4 = 84 samples

I then would like to be able to store at least four patches of sounds. So will this sampler let me store 336 stereo (stereo isn't essential, but would be nice) samples at 44.1/16 bit if each sample were an average of one second (some would be longer, but most would be shorter.

I only need I think 6 notes of polyphony at the most (we only use two mallets at a time).

Can I switch between the four banks of sound with the push of a button?

Sorry again about coming in with so many questions. I've read over the thread, and I'm afraid I just don't know enough yet to answer these questions...

PS: if you're interested in seeing what I'm talking about in action, here's a live video from a show we were recently playing (using Reason as the sound module).

Edited by mbira

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Hi,

Looks like an interesting application! It should just about be possible but you will need to get your hands dirty in the code. The project's constraints and tradeoffs are as follows:

- polyphony. This depends upon CPU speed (usually fixed at 120MHz if it's the LPC board) but also the speed of your SDcard, the length of the samples and your sampling rate (the code is set for 44.1 but other guys here use lower). By default you can get 8 notes polyphony on long samples but with shorter you could get 10,12 or more

- number of samples. By default this is 64 per sample bank (ie the number you want to play right now) so it could be possible to increase it - it depends how much memory is used on the processor. The memory is used to cache the cluster positions on the SDcard, and the longer the samples the more clusters - so trading off sample length (or lower bit rate) and you could increase the number of samples. I think you could easily go to 84 samples with no changes except the define at the top of the code which is set to 64

- velocity split. Currently the code only does amplitude modulation of the samples depending on velocity input. It should not be too hard to modify the midi receive routines to map to 4 sample sets depending on velocity, but you will have to add this code. I would recommend you build a 21 sample bank at your first velocity then add an offset for each velocity layer. The rest of the voice assignment code and sound output should work ok. You will have to make sure that if a note off is received then all the velocities are turned off. One thing you could add is to modify the bank file parsing to read in a start and end velocity for each sample (velocity layer) which would make it easier to create sound sets.

Finally, the project only currently supports mono samples. This is purely because SD cards are slow and the polyphony discussed about would be halved if using stereo sounds (though with short samples you may stretch to 5 or 6 notes polyphony with a fast SD card). You could though perhaps do something novel like only reading mono samples but mixing seperate left and right outputs and output lower note ranges on the left and upper on the right if that's useful ?

On the point about changing sound banks - yes it already responds to midi program change and i also have a rotary switch on the J10 port which directly allows selecting up to 9 sound banks at the turn of a switch.

Note that if you want to ditch the laptop, then you'll need megadrum to output real 5 pin DIN midi rather than a USB interface (as the LPC code here doesn't run the USB port in host mode). This should be trivial for you.

Good luck!

Hi guys,

I was sent to this thread, as I think I'm looking for something like this. Please pardon my newbie ignorance-I have experience building audio gear - preamps, compressors, tube amps, etc, but I'm still pretty new with this type of stuff.

I built a Megadrum, and I use it to convert audio signals to Midifrom marimbas where I put piezos in the keys. Right now, the megadrum is feeding my computer via USB and I am using Reason synth sounds.

I'd like to build an onboard hardware sample solution on each marimba and ditch the computer. I was sent here, but I'm confused if the specs I need would work if I build this.

My soprano marimba has 21 keys. I want to sample each key with at least 4 layers of velocity:

21 x 4 = 84 samples

I then would like to be able to store at least four patches of sounds. So will this sampler let me store 336 stereo (stereo isn't essential, but would be nice) samples at 44.1/16 bit if each sample were an average of one second (some would be longer, but most would be shorter.

I only need I think 6 notes of polyphony at the most (we only use two mallets at a time).

Can I switch between the four banks of sound with the push of a button?

Sorry again about coming in with so many questions. I've read over the thread, and I'm afraid I just don't know enough yet to answer these questions...

PS: if you're interested in seeing what I'm talking about in action, here's a live video from a show we were recently playing (using Reason as the sound module).

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Great. Thanks for the thorough reply! I haven't yet done enough research on the components-to be sure I understand-so the currently loaded samples in the bank get loaded into memory on the processor? Are you having to read from the SD card during performance other than when changing banks? Does that only take a few secons or a few minutes? Just making sure this will work for us on stage...Have you measured latency? Regarding stereo, maybe I can modify the code to have half the polyphony and send two samples for every hit...

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Hi, the player reads directly from the SDcard during playing and doesn't buffer in RAM - the processor only has 64kB! This actually works well but due to the speed of the card the polyphony is limited.

When you change bank, it pre reads the positions of the sample data on the card (just the positions, not the actual data) which takes about 1 second - possibly faster depending on number of samples in the bank.

Latency is fixed which at 44.1k is 5.2ms

Cheers

Great. Thanks for the thorough reply! I haven't yet done enough research on the components-to be sure I understand-so the currently loaded samples in the bank get loaded into memory on the processor? Are you having to read from the SD card during performance other than when changing banks? Does that only take a few secons or a few minutes? Just making sure this will work for us on stage...Have you measured latency? Regarding stereo, maybe I can modify the code to have half the polyphony and send two samples for every hit...

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Awesome!

Lee, you mentioned you are using a minimal setup for the processor. Do you have a link to the minimal setup? This will live in the instrument, so the less I need, the better. I have 5V coming off of the megadrum (schematic), and I can tie in to the MIDI coming directly out of the atmega and 6N138N.

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Read the section just below half way down this page: http://www.ucapps.de/mbhp_core_lpc17.html (the schematic for the full LPC based board is around there too - the minimal bit is just the obvious parts of the USB connector, power regulator and capacitors, plus a jumper for the boot hold)

And then look at the links on the top of the wiki page here for the DAC and SD card connectors: http://www.midibox.org/dokuwiki/doku.php?id=midibox_sd_card_sample_player

Awesome!

Lee, you mentioned you are using a minimal setup for the processor. Do you have a link to the minimal setup? This will live in the instrument, so the less I need, the better. I have 5V coming off of the megadrum (schematic), and I can tie in to the MIDI coming directly out of the atmega and 6N138N.

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Hi everyone,

Just a quickie to mention that the player's been featured on Hackday today: here

I did a write up on my site that's also got a bit of history and other info: here

Hope everyone's doing good!

Cheers

Lee

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Done! I got brain ache trying to remember all the details from a few months back... :smile:

Thanks again for all your help that made it a success and fun to work on rather than a frustration!

Congratulations! :)

Your report is also nice to read!

Could you please add a link to your project page: http://www.midibox.org/dokuwiki/doku.php?id=midibox_sd_card_sample_player

Best Regards, Thorsten.

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