VS1000
8
VS1000 ERRATA
8 VS1000 Errata
This chapter describes the known problems with different VS1000 revisions. Most of the prob-
lems are correctable with user code that is loaded to IRAM.
VS1000B Changes
• NAND FLASH and Ramdisk boot can have initialized Y data.
• EarSpeaker initialization fixed, EarSpeaker optimized from 12 MHz to 10 MHz (at 44.1 kHz).
• Small power-on click removed.
• User interface works even if there is no filesystem. (You can turn the power off.)
• NAND FLASH boot handles larger than 512-byte programs without a chain-loader rou-
tine (upto 8176 bytes). Ramdisk boot (VS1000_B.RUN) handles larger than 512-byte
programs (upto 8192 bytes).
• When attached to USB, LED is flashed when there is read/write activity. LED is turned off
when the file system has been flushed.
• Volume is always initialized, USB Audio Device can be powered on while attached to USB
(powered from VBUS).
• USB Suspend + Resume are implemented (but need user tuning).
• Vorbis: Now uses adaptive accuracy for windowing, implements fast play mode, and has
better synchronization after non-fatal errors. Replay gain has been fixed.
• Player: Fast play mode is used for better-sounding fast forward. Fast forward speeds up
when the ff button is kept pressed. Player uses the suspend routine to implement low-
power pause mode. Timeout turns the unit off after being 5 minutes in pause mode. The
default maximum clock in player mode is 3.5×.
• Some new IRAM hooks: KeyEventHandler, MassStorage, USBSuspend, InitUSBDescrip-
tors.
VS1000C Changes
• No changes. Has the same firmware as version B.
VS1000B/C Errata
• NAND FLASH and Ramdisk boot needs one filler word after every Y data record.
• BusyWait1() wait time equals BusyWait10() time.
• SCSI limited to 23-bit block address (4GB).
• File scan gets stuck if FAT12 disk has subdirectories. FAT12 is not used if disk is > 16MB.
VS1000D Changes
• Is backwards compatible with existing code, so can be used as a direct replacement
for VS1000b/c.
• Code can be loaded and executed when in RAM disk mode without detaching the
device.
• Default 3 V IO voltage setting reduced from 3.6 V to 3.3 V (control value 31 to 27).
• SCSI supports the full 32-bit block address (2048GB).
• BusyWait1() now waits 1 ms at 12 MHz clock.
• Time to enter low-power pause mode doubled.
• Ignores subdirectories in FAT12 disks.
• RAMDISK label changed to VS1000D_RAM to make it possible to detect VS1000D.
• USB descriptors, including device ID is the same as with VS1000B.
• Fixed-width Latin-1 font (7x8 pixels) and 8-bit bit-reverse table added to YROM.
Version: 1.4, 2011-10-06
23
ETC [ ETC ]
