Hack64.Transfer Data to and from Your Car PC


Hack 64. Transfer Data to and from Your Car PC

USB flash drives, portable USB/FireWire hard drives, and WiFi are a few of the ways to get data onto and off of your car PC.

One of the things you should know before you get an in-car computer is that you are going to have to feed it. Car computers are multimediaivorous, subsisting primarily on digital audio, video, and GPS coordinates for roughage.

Seriously, though, you are going to want to get your media into the car, and probably update it from time to time. Some people prefer to perform a onetime dump of their entire MP3 collections into their cars and leave it at that. Others want to be able to listen to daily music feeds from Podcasts (http://en.wikipedia.org/wiki/Podcasting), books on tape (http://www.audible.com), or their own email and documents converted to MP3 using computer text-to-speech synthesis (http://www.nextup.com).

Although wireless is sometimes touted as the holy grail of car-computer synchronization, 802.11a/b/g may be too slow for routine large media transfers. Also, any WiFi solution depends on your car being parked close enough to your home network to get a decent signal and requires your car PC to run when you aren't in the car, which can potentially drain your car battery.

Table 6-1 compares various ways to transfer data to your computer. Which method you choose comes down to how much data you have to transfer.

Table 6-1. Network transfer speeds

Technology

Theoretical speed (in Mbps)

Maximum (in Mbps)

Minimum (in Mbps)

Expected time to transfer a 700-MB CD (in minutes)

Expected time to transfer a 4.3-GB DVD (in minutes)

802.11b

11

5

< 1

19

117

10-MB Ethernet

10

9

3

11

63

USB 1.1[1]

12

9

4

11

63

802.11g

54

20

12

8

49

USB 2.0 flash drive[2]

480

80[3]

24[4]

4

N/A

100-MB Ethernet

100

90

70

<2

6

FireWire[5]

400

400[6]

80[7]

<1

4

USB 2.0[8]

480

350[9]

80[10]

<1

4

1-GB Ethernet

1000

500

160[11]

<1

4


[1] Technically, you should double the time, as you need to copy the data twice (once from your desktop to the portable device, and then again to the car PC). However, portable hard drives and flash drives don't require you to move the content onto your car PC's hard drive.

[2] Technically, you should double the time, as you need to copy the data twice (once from your desktop to the portable device, and then again to the car PC). However, portable hard drives and flash drives don't require you to move the content onto your car PC's hard drive.

[3] Typical hard drive data rates will vary a lot and will be the limiting factor on these speeds.

[4] Typical hard drive data rates will vary a lot and will be the limiting factor on these speeds.

[5] Technically, you should double the time, as you need to copy the data twice (once from your desktop to the portable device, and then again to the car PC). However, portable hard drives and flash drives don't require you to move the content onto your car PC's hard drive.

[6] Typical hard drive data rates will vary a lot and will be the limiting factor on these speeds.

[7] Typical hard drive data rates will vary a lot and will be the limiting factor on these speeds.

[8] Technically, you should double the time, as you need to copy the data twice (once from your desktop to the portable device, and then again to the car PC). However, portable hard drives and flash drives don't require you to move the content onto your car PC's hard drive.

[9] Typical hard drive data rates will vary a lot and will be the limiting factor on these speeds.

[10] Typical hard drive data rates will vary a lot and will be the limiting factor on these speeds.

[11] Typical hard drive data rates will vary a lot and will be the limiting factor on these speeds.

6.4.1. Flash Drives

Flash drives (Figure 6-4) are small, cheap, and possibly the easiest way to get your media into the car. Priced at around $100 for a 1-GB drive, and less than $20 for a 128-MB drive, these USB devices are smaller than a cigarette lighter yet can store up to several gigabytes of data.

Figure 6-4. A USB flash drive


Flash drives have several car-related benefits. As they have no moving parts, they are essentially shockproof, and their low power consumption makes them ideal for in-car use. Most USB ports [Hack #51] are limited to less than 500 mA of power. Though many portable USB hard drives require more power than this, USB flash drives usually don't. This means you can plug a USB flash drive into a bus-powered USB hub (i.e., a hub that gets its power from its USB connection to the computer), and you shouldn't have any problems powering the drive.

The important things to check for when purchasing a USB flash drive are that it can run on a bus-powered hub and that it supports high-speed USB 2.0 (480 Mbps, not 12 Mbps, which is known as "full speed"), so that your media will copy and play quickly.

If you've been looking for an excuse to get an iPod, the new iPod Shuffle makes a great USB flash drive.


A review of USB flash drives can be found at http://www.arstechnica.com/reviews/hardware/flash.ars.

6.4.2. Portable Hard Drives

Laptop hard drives are only 2.5" wide and are designed to withstand more vibration than 3.5" desktop hard drives. Over the last few years, compact USB 2.0 enclosures for these hard drives have made it very easy to port hundreds of gigabytes of data in your pocket. You can purchase a hard drive/enclosure combo or, if you have an old laptop drive sitting around, you can find the enclosures themselves for less than $20 at places like http://www.compgeeks.com.

The best hard drives and optical drives are bus-powered and can run right off the computer's USB or FireWire connection. However, if you are using a long (more than 15-foot) USB or FireWire cable to connect a PC in the trunk to the dashboard, chances are that your hard drives, optical drives, and other mechanical devices will not have enough power to run, especially if they go through a hub. In this case, the solution is to provide them with power directly [Hack #50].

If you don't want to copy your media onto your car PC but just want to play it, that's easy to accomplish. Most of the car PC frontends (discussed in Chapter 7) can easily, if not automatically, switch to the media on an inserted removable drive.


6.4.3. iPods and Other Portable Media Players

Apple's immensely popular iPods are also high-capacity, portable, self-powered USB 2.0 and FireWire hard drives, so they can be used to transfer anything you wantvideo includedto your car PC.

The nice thing about iPods is that iTunes automatically synchronizes the MP3 collection you have in iTunes and the collection on your iPod. Thus, it's simply a matter of plugging your iPod into your home PC for long enough, and you'll always have all of your music with you.

If you install iTunes on your car PC and plug your iPod into it, you'll be able to see your iPod in iTunes and play any non-copy-protected songs. To play songs purchased from the iTunes Music Store, your in-car copy of iTunes will need to be authorized, which requires you to have an Internet connection, at least temporarily. Click Advanced Check for Purchased Music, and type in your iTunes Music Store name (Apple ID) and password. The copy of iTunes on your car PC will connect to the store, authenticate itself, and permit you to play your purchased music on that machine as well.

If you have other media besides music, you're in luck, because the iPod also doubles as a large portable hard drive. With a 20-GB iPod, you can carry five full DVDs' worth of video, or 4080 hours of video if it's been compressed with a video compression format such as MPEG-2 or MPEG-4.

With its compact design and high storage capacity (and the fact that you may already own one), the iPod is a great tool for getting music and video from your desktop computer out to the car.

As fantastic as the iPod is, though, most of the third-party portable media players out there are just as good, if not better, at moving audio and video to your in-car PC. You can load most of them with music by just copying a directory full of music, without having to use some other music-management program.

The best portable media players for in-car use are self- or bus-powered, meaning they are powered or recharged by the USB or FireWire connection on your computer. Most flash solutions and small hard drive solutions meet this requirement. As long as they use the newer USB 2.0 standard, you should be able to play audio and video right off the device without having to copy it to your in-car computer's hard drive.

6.4.4. Portable Media Synchronization

If you're the type of user who transfers your entire media library onto your car PC once and then rarely needs to update it, auto-synchronization probably isn't that essential to you. However, if you're an avid fan of Podcasts or are constantly adding music, TV shows from your PVR, or movies to your in-car jukebox [Hack #70], you'd probably like your car PC to pull these files from your portable hard drive or desktop PC automatically.

Some brands of USB flash drives come with synchronization software. Flash drives from Iomega (http://www.iomega.com) come with Iomega Sync, which is designed to automatically keep files and folders synchronized between the desktop and the drive. It can even be configured to keep two computers in sync, using a single drive moved back and forth between them. Naturally, this software only works for Iomega drives.

Most of the synchronization apps I have found are pretty useless for the kind of automated synchronization you'd need for a car (i.e., no dialog boxes popping up). The best I've found so far is ZincSync (http://www.zincsync.com). It has a nice feature for automatically "backing up" an inserted flash drive or other removable hard drive to a specified directory (without overwriting what is already there). I made my "backup" directory the "My Music" folder in My Documents, inserted my flash drive, and voilà. It immediately began syncing just like I want it to when I plug it into my car PCwithout asking. A very nice utility.

6.4.5. WiFi/Lan Synchronization

Using a program by Karen Kenworthy called Karen's Replicator, you can automatically sync your car PC with your home media library over WiFi. This program (including Visual Basic source code!) can be found at http://www.karenware.com.

To make synchronization automatic and seamless, you need connectivity between the two computers, which means you need a wireless network set up in your house that you can access from your car when it's parked in the driveway or garage. The faster the network the better, because media files (especially video files) are big [Hack #70]. If the distances involved are great enough, you may need to get a wireless network extender or put a wireless base station as close to the driveway as possible (maybe even in your garage).

If you really need fast transfer, you can park in your garage and plug an Ethernet cable into your car PCkind of like filling it up with gas, but filling it up with digital media instead.


Once you have your network extending to where your car is parked, you need to configure networking so that your car PC can see your home file server, where your media files are stored. On the car PC, you should map persistent network drives to the server directories you want to sync with (check the "Reconnect on login" box when creating the share in Windows), so that they will automatically reconnect when the computer is rebooted. (This is a feature of Windows, not of Karen's Replicator.)

Once you can access the file shares, it's time to set up Karen's Replicator. Run the program, and go to Edit Settings New Job. Browse for the file folders you want to sync, and create any filters or extra rules you want to apply (for example, exclude *.mp3).

Click Schedule, and set all the timer options except minutes to 0 (I recommend setting minutes to 2). Make sure you set the beginning time to something soon, so you won't have to wait long for it to go into effect. Click Save, then Save Job, name the job, and click Close and Save.

Here is the cool part: with these settings, your car PC will attempt to sync every two minutes; if it doesn't find the network, it will fail silently. This means that when you pull up to your house, within two minutes it will find your network and automatically synchronize the folders you've selected!

If you set up your computer to stay on for a while when you go in the house [Hack #43] or boot up on a schedule [Hack #47], you can simply park, go into your house, and trust your computer to sync unattended and shut off shortly afterwards.

If you prefer to do the synchronization manually, don't schedule automatic syncs in your jobs. Instead, choose a job and click "Run Highlighted Job Now" when you want to sync.

FrodoPlayer [Hack #75] comes with a special version of Karen's Replicator with large, touchscreen-compatible buttons (see Figure 6-5). If you are running FrodoPlayer, you can simply click on the main menu and choose "SYNC".

Figure 6-5. KarenWare synchronization software with Frodo-sized buttons


You can set up additional jobs to synchronize multiple folders, if you like. I think it's a really cool way to keep a car PC up to date, and it certainly beats burning CDs full of media that must be manually uploaded to the car computer. One thing to remember, though, is that wireless networks aren't very fast, so you may want to transfer the bulk of your media to your car PC by directly connecting the drive to your server or using higher-speed Ethernet or FireWire networking.

6.4.6. See Also

  • "Get Online in Your Car" [Hack #62]

Kevin "Frodo" Lincecum, Jacob Riskin, and Damien Stolarz



    Car PC Hacks
    Car PC Hacks
    ISBN: 0596008716
    EAN: 2147483647
    Year: 2005
    Pages: 131

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