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Sonic Alert 2.8 user manual December 28

Models: 2.8

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5.3 Linux Support

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5.3.8Notes about userland root filesystems

Section 5.3.6 refers to the cramfs target without really indicating its’ use. The cramfs option is one of three primary ’bundled’ targets:

1.cramfs - Creates a single file as a read-only, gzip-compressed image of a filesystem tree. When you can nail down the content of your filesys- tem, this is a great choice, providing the fastest boot time (around 7 seconds on a PXA-255) and complete immunity to corruption. This filesystem is often used in conjunction with read-write filesystems (ram disk for volatile data, or VFAT for semi-static data).

Requires cramfs support in the kernel (Miscellaneous Filesystems—Compressed ROM file system support).

2.jffs2 - Creates a single file as a read-write, gzip-compressed image of a filesystem tree. This is useful for placement in flash, and is fairly immune to corruption at the cost of extra time for validation at boot (typically 30-45 seconds for a 32MB filesystem).

Requires JFFS2 support in the kernel (Miscellaneous Filesystems—Journalling Flash File System v2 ).

3.mmcinitrd/mmcinitrd.u-boot - Creates a single file as a read- write, uncompressed image of a filesystem tree suitable for use as an initial RAM disk (initrd).

It requires the following options in the kernel:

Loopback device support Device Drivers—Block Devices Initial RAM Disk support Device Drivers—Block Devices

In addition, this target makes a bunch of other choices for you. Since this is a bit involved, discussion of the steps is deferred to Section 5.3.9.

The Makefile instructions for each of these is at the tail-end of the userland Makefile (userland/Makefile).

Refer to that file for details, but the bundled image for each is created by performing a single command specifying an output file (the image), a path name to a directory tree, and the devices.txt file.

Typical usage for the initrd target is to have the boot loader load the image into RAM. Das U-Bootprovides support for handing the load address to the Linux kernel through the bootm command.

Both the cramfs and JFFS2 images may also be mounted directly from flash EEPROM using Linux MTD block devices. U-Boot’s support for passing

December 28, 2005

Revision 2.8

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Sonic Alert 2.8 user manual December 28
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2.8 specifications

Sonic Alert 2.8 is a state-of-the-art alarm clock designed primarily for individuals with hearing impairments or those who simply require a more robust waking mechanism. Engineered to deliver high-performance features and proprietary technologies, this device stands out as a reliable solution for a restful night and an efficient morning wake-up.

One of the hallmark features of Sonic Alert 2.8 is its powerful bed shaker. This vibration mechanism is designed to be placed under your pillow or mattress, providing a tactile wake-up signal. For individuals who may not respond to traditional auditory alarms, this function ensures that they start their day without being late for appointments or commitments.

The alarm clock also boasts an impressive sound output. With adjustable volume settings, users can customize the alarm sound to their preference, ranging from gentle melodies to loud, attention-grabbing beeps. This flexibility caters to diverse user needs, allowing for a more personalized waking experience.

In terms of visibility, Sonic Alert 2.8 integrates a bright, flashing strobe light that works in conjunction with the auditory alarms. This visual cue appeals to those who may have difficulty hearing and can be beneficial in noisy environments. The strobe light can be set to flash in a specific pattern or color, adding another layer of customization to the waking experience.

Moreover, Sonic Alert 2.8 is engineered with a user-friendly interface, featuring large, easy-to-read display numbers that are perfect for the visually impaired. The intuitive buttons allow for straightforward operation, including setting alarms or toggling through various functions with minimal hassle.

The device is also equipped with a battery backup feature, ensuring that alarms will still sound even during power outages. This functionality provides peace of mind, knowing that important morning engagements won't be missed.

Additionally, Sonic Alert 2.8 is constructed with durable materials, making it a reliable companion for years to come. The sleek design and compact size make it easy to place on any bedside table without taking up excessive space.

Overall, Sonic Alert 2.8 exemplifies innovation in alarm technology, combining advanced features and thoughtful design to cater to users' unique needs. Whether for the hard of hearing or anyone who simply desires a more effective wake-up method, this alarm clock is an ideal choice.