Atmel AT89C51SND1C, Руководство пользователя

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Operating Description
3-18 Firmware Package User Guide
4209A–MP3–12/02
3.8 Download
Operating Mode
Firmware V2.0.X and later support USB mass storage on the following platforms:
n
Win98 through Atmel drivers
n
Win2000
(1)
/ME/XP
n
MAC OS
(1)
V9 and later
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Linux
Note: 1. These platforms do not provide multi-drive support
When the development board is plugged to the host through the USB cable, the cur-
rently selected operating mode is stopped and the download operating mode is entered
(see Figure 3-7). When disconnecting from the host, the song operating mode is auto-
matically selected.
Depending on the platform multi-drive support, one or two removable disks automati-
cally appear in the explorer window. Content of the selected memory is then made
accessible for read/write operations through the explorer.
Figure 3-7. Display in Download Operating Mode
3.8.1 Keypad Functions As soon as development board is connected to the PC, player is not controllable
through the keypad until it is unplugged from the PC.
3.8.2 Memory Selection Memory selection is done when entering the download operating mode.
On platforms that do not support multi-drive, the selected memory (refer to icon) is:
n
the MMC if at least one MMC card is present in the stack
n
the on board memory if no MMC card is present in the stack
The selected memory stays selected until USB is unplugged.
On platforms that support multi-drive, the selected memory is:
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the on board memory on the first mounted drive
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the MMC on the second mounted drive
When MMC card is removed and plugged again, and depending on the operating sys-
tem, it may be necessary to press the F5 key to refresh the explorer content.
3.8.3 Write Protection If keypad is locked before entering the download operating mode, file write will be forbid-
den and a message will inform user that the device is write protected in case of
attempted file write. Due to SCSI mass storage implementation, write protection must be
set prior to connecting the device to USB. Any change of the lock key during connection
will have no effect.
3.8.4 Download State The download or upload activity is signalled to user by blinking the download indicator.
Do not unplug the player while this indicator is blinking, this may result in file system cor-
ruption and may request new formatting of the memory.
USB
Download Indicator
Icon
Memory
Icon
Write Protect Status