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--- midibox_sd_card_sample_player [2011/12/11 18:17] – leeby5
+++ midibox_sd_card_sample_player [2012/05/29 21:14] (current) – leeby5
@@ Line 1: / Line 1: @@
 ====== MIDIbox SD Card Polyphonic Sample Player ======
-This is a brief description of a project in progress to play back samples in real time from an SD card to an I2S based DAC on the Midibox. It will play a number of samples simultaneously, mixing the output to the DAC, the number of samples depends upon the performance of the SD card.
+This is a brief description of a project to play back samples in real time from an SD card to an I2S based DAC on the Midibox. It will play a number of samples simultaneously, mixing the output to the DAC, the number of samples depends upon the performance of the SD card.
 ===== Hardware =====
 You will need:
-  * Midibox LPC1769 core - see http://www.ucapps.de/mbhp_core_lpc17.html (or make a minimal setup like I did)
+  * Midibox LPC1769 core (or STM32 now, but that has limited polyphony due to core speed) - see http://www.ucapps.de/mbhp_core_lpc17.html (or make a minimal setup like I did)
-  * I2C DAC (ie TDA1543) - see http://www.ucapps.de/mbhp_i2s.html but MAKE SURE YOU RUN THE TDA1543 DAC FROM 5V AS 3.3V SOUNDS BAD
+  * I2C DAC (ie TDA1543 or similar) - see http://www.ucapps.de/mbhp_i2s.html but MAKE SURE YOU RUN THE TDA1543 DAC FROM 5V AS 3.3V SOUNDS BAD
   * SD card interface - see http://www.ucapps.de/mbhp_sdcard.html
   * SD card formatted as FAT (NOT FAT32 - important as FAT32 performance currently isn't fast enough) - this limits you typically to cards <=2GB
   * MIDI data via USB or the standard Midi in
-I have currently only tested this on the LPC1769 based MIOS32 Midibox. It should work in theory if compiled for the STM32, but I don't have one to try!
+It has now been run on both LPC1769 and STM32 cores... :-)
 ===== Creating files on SD card =====
@@ Line 47: / Line 47: @@
   * You can do sample hold per sample, eg have a bank where drum sounds are on some notes, and other non-hold samples such as bass are on other notes
   * It now supports velocity sensitivity, and this is translated to volume via a look up table
-  * Bank switching is supported on the fly (ie without a reboot) - though program change isn't there yet
+  * Bank switching (MIDI program change) is supported on the fly (ie without a reboot)
   * Thanks to TK the sector positions on the SD card are cached leading to much better stability with multiple notes sounding
@@ Line 57: / Line 57: @@
   * Now uploaded to the MIOS32 SVN at:
   * [[http://svnmios.midibox.org/listing.php?repname=svn.mios32&path=%2Ftrunk%2Fapps%2Fsynthesizers%2FSD+card+sample+player%2F]]
+===== More info =====
+  * A write up and more info on my site at [[http://www.bassmaker.co.uk|Bassmaker]]